Very comprehensive paint knowledge, recommended collection!

01
why is it best to use primer for bottom filling in the paint process?
Because the primer is designed for the main purpose of filling, it has excellent filling and polishing, and the cost is low, and if the finish is used to fill the bottom layer, the filling effect is poor, and the cost is high.
not
wood eyes with transparent putty in the 02-minute bottom coloring process?
before coloring, use transparent putty, which will make the sheet colorless. If transparent putty is used after coloring, it can affect the uniformity of coloring due to uneven thickness and thickness of the putty

.
should
be taken into account in the bottom coloring coating process?
(1) wipe the face of the cloth, try to choose cotton white cloth.
(2) to wipe the base color, the colorant should be applied evenly to the surface of the material, 2 or counterclockwise. In the direction of the straight wood grain will be redundant wipe clean, even finishing.
(3) If the material quality is poor, apply a thin brush of the lower viscosity head.
(4) bottom coloring, the first time you apply primer can not Taiyuan, so as not to color flowers.
04
why do primers have to be thoroughly polished before coating the finish?
to enhance its adhesion, the paint has a strong follow-up, such as the primer uneven, then the paint coating, the coating effect is poor.
the
standards for thorough polishing of the primer on the 05th floor?
450 angle to see the lightless bright spots;
the
the number of years the primer brush has been applied?
should completely fill the wooden eye. That is, by polishing can get a flat paint film effect.
07
how can I avoid surface flowering when painting silver powder?
paint viscosity can not be too low;
are
requirements for the coating environment in 2008?
(1) the optimum environment should be 15-25 degrees C, the minimum temperature should not be lower than 5 degrees C, the maximum temperature should not be higher than 35 degrees C
(2) temperature the optimum ambient humidity is 30-70%
(3) ventilation equipment to be Good
(4) to ensure environmental cleanliness
(5) lighting is good and adequate
(6) should pay attention to electric fire and paint can not be too close
09
before coating the material requirements?
(1) should be kept between 8-10% of the wood when coated.
(2) wood glue on the wood surface is sanded clean with sandpaper.
(3) the temperature of the wood must be similar to the ambient temperature at the time of coating.
(4) wood surface to be clean, should be sweat-free, oil and other impurities.
10
why does PU paint emphasize the use of main paint, curing agent, diluent?
different PU paints, have different dilution systems, and have different solid content. If the use of non-matching thinners or curing agents, it will affect the cross-linking reaction of the paint, resulting in insufficient hardness, dryness, film cracking and other problems.
11
. Why does PU paint emphasize proportional ratio when provisioning?
the ratio of PU paint to curing agent is calculated by chemical reaction molecular formula. Proportions should be strictly controlled. If you add more curing agent, the paint film is brittle and burst. When the construction is prone to bubbles, the gloss is high. If less curing agent paint film hardness is not enough, poor scratch resistance, slow dry or even dry.
12
color paint coloring can not use color refinement?
because the color composition in solid paint is mainly pigment composition. Chromosomy is made up of dyes with no cover. If the color refinement is used in the solid color paint color, the tone is not obvious, and easy to produce floating color, in the solid color paint color application mother.
do
need to stir thoroughly during the 13th paint construction?
paint is a mixture of resins, pigments, solvents, etc. It is not a solution. The pigments, the primer powder in the varnish, etc. are scattered in the paint liquid. Therefore, usually in the storage process will have a certain degree of subside, the formation of the usual paint layering. So the paint needs to be stirred thoroughly before mixing. (Must be stirred paint is: varnish, transparent colored surface, solid paint, beautiful paint, wood-print treasure)
14
a brief description of the reasons and solutions for paint color change


(2) use an easy-to-fade paint.
(3) high temperature drying decoloration.
(4) light paint is directly exposed to UV rays.
: The
(1) paint is matched correctly.
(2) use high-quality paint.
temperature is too high when the temperature (3) is dry.
(4) the use of UV-resistant coatings can reduce the degree of color change.
15
do you think of paint yellow resistance?
paint yellowing is a paint characteristic, not a disease. Therefore, the yellowing of the paint is relative and not absolute. PU paint, generally yellow-resistant and yellow-resistant paint, usually light-color plate selection of yellow-resistant paint, dark plate selection of general yellow-resistant paint. Methods to reduce the degree of yellowing:
(1) the selection of yellow-resistant paint can reduce the degree of yellowing.
(2) to strengthen furniture maintenance measures (e.g. waxing, etc.)
(3) heating temperature can not be too high (60 degrees C below)
16
Spray nitro paint (NC) paint film why whitening, how to prevent whitening?
coating in the film after the paint film presents turbid or milky white phenomenon called paint film whitening, also known as whitening, whitening, al whitening and so on. The reasons for the whitening of the paint film when the nitro paint is sprayed are as follows:
(1) The nitro paint itself has very good solvent release, the solvent evaporates into the atmosphere in NC paint, which is easier than in other paints;
(2) NC paint formula contains more volatile faster solvents;
(3) if the high temperature environment, solvent volatile faster;
(4) solvent rapidly volatile, absorbing the newly sprayed NC paint film wet film internal energy, so that the wet film surface temperature dropped 2-30 degrees C, providing a "condensation" occurred in the "cold bed";
(5) high temperature and high humidity environment, so that the wet film around the high content of water vapor quickly condensed into micro-water droples on the
"cold bed";
above 1, 2, 3 is a prerequisite for whitening, 4 is the intermediate process, 6 is the final result. After the whitening phenomenon occurs, some appropriate warm-up (e.g. with light) can make the whitening disappear and recover as before. Some are irreversible, always white, the reason is unknown.
17
to prevent paint film "whitening" can take the following measures:
(1) coating environment temperature to 15
-250 degrees, the relative humidity of the environment should not be greater than 75%;
(3) pay attention to take as far as possible higher quality paint and Tianna water,
(4) when high temperature, high humidity environment, the construction of whitening phenomenon, can be added slow-dry solvent, so that the surface of the wet film solvent evaporation speed is reduced, not to let the "cold bed" form.
(5) use the correct method to keep the indoor coating environment in line with the requirements. Outdoor yellow plum rainy day, but the big door and window "ventilation" is wrong. Outdoor rain, humidity drop, but indoor will still be wet, a few days do not dry, this is the result of water and gas easy to enter and out, at this time open doors and windows, and even forced ventilation is right.
does
run oil occur in the 18-year-old spray construction?
coating shrinks on the surface of the coating, forming shapes like balls, pinholes, etc. of varying sizes, such as water spilled on wax paper, spots reveal the bottom layer, a phenomenon known as "running oil." Also known as "laughing." PE paint has a higher risk of running oil. The cause of "running oil" is caused by the poor wetness of the coating on the applied surface or the high surface pressure.
the reasons for the production of running oil are as follows: (1) the bottom layer or paint mixed with oil, wax, moisture, affecting the adhesion of the paint film, paint film surface tensor pressure so that the paint film shrink running oil. (2) The underlying coating contains non-drying thinners, such as kerosene, diesel oil, drying after not evaporating in time on the paint. (3) The underlying paint is too smooth, and the adhesion of the surface layer is less than the surface pressure of the surface coating to produce running oil. (4) Poor wetting of the coating or mixed with too much silicone oil, are not easy to form a uniform film layer, easy to run oil. (5) Spray room air pollution, such as spray room around the polishing, acid vapor evaporation and other processes of the factory (such as shoe making, pickling, electroplating), with the change of wind will be oil, acid blow into the spray room, so that the paint film running oil.
treatment of running oil methods: (1) to deal with the grass, coating must not have oil, wax, moisture and so on. To check the separation effect of oil and water separator, check whether there is oil and water vapor in the gas route, if there should be treatment clean and then spray construction. (2) Paint construction viscosity should be moderate, and choose a less volatile solvent, such as winter thinner for summer diluent. (3) Try to avoid construction in cold, humid, smoky environment, spray room should not be built in the polished, acid vapor volatile factory near. (4) The amount of silicone oil in the paint should be appropriate, excessive doping will produce running oil. (5) When the construction found that there is running oil phenomenon, should immediately stop the construction, check the reasons for running oil, excluding the construction. (6) has appeared running oil work, should be all done and then polished flat, and then reapplyed.
bubbles
pinholes occur during the 19th spray construction?
spraying construction produces bubbles, pinhole analysis is as follows:
phenomenon: in the coating surface first appeared a lot of much less bubbles, and then bubbles cracked or worn in the paint film grinding to form a dense linen like pinhole-like small holes.
cause: the coating contains gases (solvent vapor, water vapor, expanding air or other gases that can be mixed into the paint, such as carbon dioxide, etc.) breaking through the coating to form bubbles, which in turn break or break to form pinholes. When the surface of the coating is dry slightly faster than the inside, the surface begins to condense and the internal solvent or air continues to evaporate, it breaks through the coating surface to form bubbles. This is related to the following conditions: coating sticky too high, a thick coating, wood catheter thick, filling falsely contains air, spray air pressure is too high, too much air mixed into the paint, coated surface attached oil, dust, sweat, etc., these unclean materials around the assembly of moisture, paint and the temperature difference between the applied surface is too large, thinner improper use, Curing agent added excessive or used wrong curing agent, coating ambient temperature is too high or relative humidity is too high, the drying of the coating is not completely applied, the coating is rapidly drying, when the use of heating drying coating, the temperature is too high, the coating before heating the static time is not enough, the solvent is not fully volatile, the paint itself into the bubble, the bubble produced when stirring is not eliminated and so on.
Exclusion method: check the coating process conditions for the above reasons, adjust the viscosity of the suitable coating, with the appropriate amount of thinner, curing agent, control the thickness of the coating; Mixing, improving the working environment, controlling suitable temperature and humidity, appropriate lengthening and re-painting time, so that the lower layer is dry enough, after the paint is conditioned to be left to be sprayed after 20 minutes, when using a heated drying coating, the control of the sit-in time so that the solvent is fully volatile and preheating the coating.
20
the component requirements and environmental conditions suitable for crack paint?
paint can be sprayed with crack paint in different shapes, such as (1) planes, surfaces and other shaped shapes.
(2) the water content of the white blank must conform to the local balanced water content.
(3) flat or surface one-time continuous spraying area can not exceed 2 square meters, otherwise should be block construction.
(4) construction site should be well ventilated, adequate light, convenient to observe the effect.
(5) construction site should be convenient for construction personnel to walk freely, can not have too many obstacles, high-altitude construction should be set up scaffolding, in order to facilitate the construction staff to move around freely.
is
21 crack paint is not cracked?
(1) crack paint or nitro-bright varnish coated after the paint film is not smooth and plump enough;
(2) crack paint or nitro-bright varnish drying time is too long;
(3) spray crack paint when the air pressure is too large, the oil volume is too small or the spray gun is too far away from the surface;
(4) construction negligence, after the paint tank is not fully stirred.
are
the construction of crack paint on the 22nd?
(1) crack primer, try to base it with a two-part coating.
(2) cracked bottom should be selected with a single-part coating. (Mainly in NC class or specially equipped crack bottom)
. (3) the speed of the gun, the distance between the same, and to grasp the amount of exhaust and oil.
(4) the same crack effect paint construction viscosity should be unified.
(5) spray crack effect paint construction viscosity should be unified.
(6) air compressor air pressure should be consistent, not large and small. The gun calibre is 1.5-2.0mm. The outing should be smooth.
(7) mask light, varnish coating master thin spray many times (divided into secondary coating).
(8) crack pattern is by the paint film evenly cracked and presented, do not spray too thick, otherwise will not crack, should be careful to control the amount of oil and the number of guns to choose the best pattern. (Before the crack has been terminated during spraying, it can be resquirted on the crack to control the crack size.) On the first spray, try it on a small plate).
(9) with crack paint should be used up within 4 hours.
23
what needs to be noted when using PE series coatings?
In the use of PE series paint, promoter and trigger can not be directly mixed, storage process, promoter and trigger to separate 2 places, after painting, tools must be cleaned, can not be used insect glue paint or nitro paint as a closed primer, will affect adhesion, after mixing in particular 25 degrees should be used up within 15 minutes, the above is a matter to be noted.
is
24 paint cracking caused?
paint paint hard through the high, poor flexibility, coating too thick, no dry through the coating layer, too much drying agent, surface drying, coating does not match, the hardness of the bottom layer difference is too big, paint expired, pigment and resin layering, stirring is not easy to crack, the environment is bad and other reasons.
25
is hung by which original.