217. What problems should be paid attention to when using and storing corona-discharge treated polymers?
Answer: Polymers such as corona-discharge treated membranes should avoid contact with metal objects. Once in contact, the treatment effect will disappear. If it must be in contact with a metal roll or the like, the roll must be covered with a plastic film. In addition, the corona discharge treated film changes its wetting ability with storage time. The longer the storage time, the more wetting ability is reduced, or even completely disappears, so it should be used in time.
218. What kinds of polymers are used mainly for flame treatment?
A: Flame treatment is commonly used in polyolefin moldings, such as surface treatment of various containers to improve their adhesion to the ink. It is also used for the surface treatment of polyethylene, polypropylene, polyoxymethylene and its copolymers, polyethylene terephthalate, and plastic sheets with a thickness of 0.6 mm or more.
219. How to wash plastic surface dust and general pollutants?
Answer: The dust and general pollutants can be cleaned with tap water, alkaline water, and emulsifiers.
220. What is the role of cleaning plastic surfaces with solvents?
Answer: Cleaning the plastic surface with the corresponding solvent can remove the surface contamination of the substrate without changing the surface properties of the substrate.
Some uses?
Answer: It is mainly used for packaging products. Such as rust-proof aluminum alloy, corrosion resistance, good polishing, long-term preservation of the appearance can still maintain light, used for canning.
233.Aluminum alloy sheet surface how to deal with before printing?
A: The surface of the aluminum alloy sheet can be cleaned with chromate and sulphate before printing to remove surface oil stains and improve adhesion to the coating.
234. What are the uses of aluminum foil?
A: Aluminum foil can be directly printed, colored, embossed, surface coated, sizing, painted, or processed into composite materials with plastics and paper.
221. What is the effect of chemical etching on the surface of printing materials?
A: Chemical etching is the application of reactive chemical substances on the plastic surface to chemically change the surface, remove some of the material on the surface to form a fine rough surface, and thus play a role in changing the surface wettability and adhesion.
222. Polyethylene, polypropylene commonly used chemical etching methods are there?
A: Polyethylene and polypropylene are commonly used screen printing materials. They are mostly surface-treated by sulfuric acid etching and chromic acid etching, and are particularly suitable for plating plastic surfaces.
223. What are the advantages of plasma treatment of plastic surfaces?
A: The advantage is that it only acts on the plastic surface, because most of the plasma induced reaction is performed at a depth of less than 1 μm in the surface layer, so the desired interface properties can only be obtained on the surface without affecting the material properties of the inner layer. .
224. Why is static electricity generated?
A: The cause of static electricity is frictional electrification or contact electrification. When two materials are contacted or separated, one material has greater electrophilicity and electrons are transferred to the surface of this material. The surface that gets the electrons is negatively charged and loses the positive charge of the electrons. The amount of static electricity generated is related to the degree of contact between the two, the speed of separation, the size of the friction force, and the conductivity of the material.
225. What are the antistatic agents for plastics?
A: There are two types of antistatic agents used in plastics. One is the most commonly used surfactant. Antistatic layer can be formed on the surface of the material by spraying or coating. This kind of coating is easy to absorb moisture. After absorbing moisture, it will increase the conductivity of the plastic surface, resulting in static charge diffusion; the second type is to incorporate antistatic agent into the plastic resin to make the surface of the finished product conductive before molding. Improve ability.
226. Which static removal device can be used for continuous printing of plastic sheets?
A: The static electricity on the plastic sheet can be eliminated by passing the plastic sheet through two specially-rotated special rubber rollers. Because the rubber contains enough antistatic agent, static electricity on the plastic can be removed.
227. There are several kinds of commonly used metal printing materials?
A: The commonly used screen printed metal substrates include tin plated steel, chrome plated steel, low carbon steel plate, aluminum alloy plate, and aluminum foil.
228. What is the characteristic of the tin plate structure?
Answer: The tin plate is composed of steel base, tin-iron alloy, tin layer, oxide film and oil film. The substrate made of steel plate can improve the processability of the tin plate, and has good strength after can making; the tin-iron alloy layer has corrosion resistance and thick layer processing; the tin layer is beautiful, easy to weld, corrosion-resistant and non-toxic. Oxide film has anti-rust, anti-discoloration and anti-stenosis effect; oil film has lubrication and anti-rust properties.
229. What are the main factors affecting the coating and printing of tinplates?
Answer: When the tinplate is coated and printed, the adhesion of the tinplate coating to the printing ink is the main factor affecting the printing quality. The factors affecting the adhesion of the coating mainly include the formulation of the coating, the surface finish of the tinplate, the state and parameters of the tin oxide film, and the like.
230. What is the structure of chrome plated steel? What are the characteristics?
A: The chrome-plated steel sheet is composed of a steel substrate, a chromium layer, a chromium oxide layer and an oil film layer, and has good processability; it has the necessary strength after canning; the metal chromium layer has a certain corrosion resistance, but is inferior to the pure tin layer. The chromium oxide layer has the function of protecting the metal chromium layer, which is convenient for coating and printing, and can prevent the generation of holes; the oil film has rust prevention and lubrication.
231. What are the uses of low carbon steel sheet?
A: Low-carbon steel sheet is mainly used for manufacturing metal packaging containers, and is also a common material for packaging screen printing. The paint black iron skin has been used in the manufacture of food and beverage cans and glass bottle caps.
232. Aluminum alloy sheet which answer: mainly used for packaging products. Such as rust-proof aluminum alloy, corrosion resistance, good polishing, long-term preservation of the appearance can still maintain light, used for canning.
233.Aluminum alloy sheet surface how to deal with before printing?
A: The surface of the aluminum alloy sheet can be cleaned with chromate and sulphate before printing to remove surface oil stains and improve adhesion to the coating.
234. What are the uses of aluminum foil?
A: Aluminum foil can be directly printed, colored, embossed, coated on the surface, sizing, painted, or processed with plastic, paper into composite materials.
Source: Ke Yin Media