Plastic Spray PU Varnish Infrared Tunnel Furnace

• Transport Package: Plywood
• Specification: 16000× 1800× 1600mm
• Origin: China(Mainland)
• Model NO.: TM-IR-P801500
• Production Capacity: 50000pieces/Year

Product Description

Cuisson: cuisson de l'apprêt, temps de cuisson 10-15 minutes, température 55-65 degrés
Topcoat Spray: Spray de finition immédiatement après la cuisson
Cuisson à l'infrarouge: cuisson à 45-50 degrés pendant environ 5 minutes
Cuisson au four UV: l'énergie est de 5000 mJ / cm 2
Cuisson III: Lorsque le four UV n'est généralement pas nécessaire pour cuire III, du PU, mais que le four UV doit continuer à cuire pendant environ 20 minutes.



The difference between UV paint and PU paint treated plastic surface is as follows:

1, the paint is different

The pU lacquer represents a polyester coating.

UV paint, the raw material is epoxy resin.

2, different curing methods

pU paint is a natural film-forming film that can be dried and cured at low temperatures without the need for special processes.

UV paint needs to be cured by strong UV light drying.
The process is different. The photocuring process used in U v paint is non-polluting when painting, and it is more environmentally friendly than Pu paint. From the factory processing technology, it is good for the protection of workers' health and environment. From the production point of view, it is a kind of Updated products. However, for the consumer, the product has evaporated the solvent in the paint surface during the processing, whether it is the U v paint produced by the photocuring process or the Pu paint produced by the traditional process. The user constitutes a pollution hazard.

3, the film thickness is different

The PU paint film is thin but not very hard.

The paint film produced by UV paint has a high hardness and a thickness of 0.6 cm.

From the technical point of view, the gloss of U v paint is better.

From the point of view of use, U v paint has better hardness and wear resistance than pu paint.


PU coating

Polyurethane coating (PU) is called polyurethane. It is a polymer compound containing -NHCOO-unit in its molecular structure. The unit is made up of isocyanate and hydroxyl. The reaction formula is as follows:

-N=C=O+HO→-NH-COO

In the 1970s, Germany first synthesized PU. Around 1950, PU appeared as a textile finishing agent in Europe, but most of them were solvent-based products for dry coating finishing. In the 1960s, water-based PU coatings emerged as a result of increased environmental awareness and the introduction of government environmental regulations. After the 1970s, water-based PU coatings developed rapidly, and PU-coated fabrics have been widely used. Since the 1980s, breakthroughs have been made in the research and application of PU. Compared with foreign countries, domestic research on PU textile finishing agents is relatively late. Polyurethane coatings are the main type of development today.



Its advantages are:

a, the coating is soft and elastic;

b, the coating strength is good, can be used for very thin coating;

c, the coating is porous, has moisture permeability and aeration performance;

d, wear-resistant, moisture-resistant, dry-cleaning.



The disadvantage is that:

a, higher cost;

b, poor weather resistance;

c, water, heat, alkali to be hydrolyzed.

The PU coating agent is classified into a polyester type polyurethane, a polyether type polyurethane, an aromatic isocyanate type polyurethane, and an aliphatic isocyanate type polyurethane. According to the medium used in the use, it is divided into solvent and water.

Solvent type

PU coating adhesive

Solvent-based PU has good tensile strength and water resistance, but is highly toxic and easy to burn. In terms of components, it is also divided into two-group classification and single-group classification. The two-component product consists of a prepolymer and a cross-linking agent, which is a hydroxyl-terminated prepolymer formed by reacting an isocyanate with an oligomeric polyol. The crosslinking agent is a compound containing a plurality of (three or more) isocyanate groups. When the coating is finished, the prepolymer reacts with the crosslinking agent to form a thermosetting network film, which imparts excellent properties to the textile. In order to achieve the effect of waterproofing and moisture permeable, the solvent-based coating finishing agent generally processes the fabric by a wet coating process.

Water system

PU coating adhesive

The water system is divided into two types: water-soluble and water-dispersible. The water-based PU is used for fabric coating finishing, and the volume is large. The water system PU has good film forming properties and good water repellency.

The water-based PU coating adhesive is initially produced by phase inversion emulsification, but the product contains an emulsifier, which has an adverse effect on adhesion, toughness and water resistance. In order to solve this problem, in the late 1980s, the self-emulsifying water-based coating gel gradually increased. The main principle was to introduce an appropriate amount of hydrophilic groups on the polymer chain and spontaneously disperse to form an emulsion under certain conditions. Waterborne PU coatings are commonly used in dry coatings. In order to improve the water resistance, softness and durability of the coated products, front and back waterproofing should be carried out.

PU macromolecules contain a large number of polar groups, and the intermolecular force is strong, resulting in excellent film-forming property, forming a tough and durable film on the fabric, good water repellency, and also having a certain moisture permeability. The reason is: on the one hand, the polar group or hydrophilic group in the PU, such as -OH, -NHCOO-, -SO3H, -COOH, etc. "chemical stepping stone", so that the water vapor molecules are high along the ladder The humidity side migrates to the low humidity side; on the other hand, the PU is composed of a soft segment and a hard segment, respectively forming an amorphous region and a crystalline region in the structure. Since the molecular chain in the amorphous region is relatively loose, the structure is not tight, and the water molecules are easy. Enter, and migrate and spread to achieve moisture permeability.

PU emulsion

modified

In order to improve the emulsion and film properties and expand the application range, it is necessary to appropriately modify the PU emulsion. At present, the ways of modification can be roughly divided into four categories:

a, improve the monomer and synthesis process;

b, adding additives;

c. Implement cross-linking;

d. Optimize the composite. Among them, the research on compound emulsion is the most active.

Difference PA vs PU

PA white and PU white or PA and PU transparent glue are difficult to distinguish from the outside, but PA and PU are still different.

One is the feel: the feel of the PA is relatively smoother than that of the PU, and the elasticity of the PU is better than that of the PA;

One is gloss: PA has no luster, PU is shiny and bright; another PU has a good film feel, and it feels like a film.

In short, PU is brighter, more elastic, and has a film feel, and PA does not have these conditions.




Of course, it is difficult to distinguish these general novices. Right, teach you a little trick: 1. Press the rubber on the cloth and lift it up. The PA will stick with the rubber and the PU will not stick. . 2. Drop a few drops of toluene on the coated surface of the 2 pieces of cloth (if possible), then gently rub it by hand (pay attention to the protection, do not directly touch the toluene), the PA coating will fall, the PU will not fall. .

The reason for dividing the PA and PU is mainly based on the coating requirements of the desired fabric.