Postpress Technology 1000 (492-509)

492. What are the natural resin adhesive materials?
A: Natural resin binders for binding are mainly rosin powder and shellac.

493. What is Rosin Powder Adhesive?
A: Rosin powder is a resin obtained by cutting from pine poles. It is made by crushing and grinding. Its main component is rosin acid. Rosin is a yellow crystalline glassy substance that is insoluble in water and soluble in organic solvents such as alcohol and ether. Rosin melts when exposed to heat and has a strong binding ability but is brittle.

494. What kind of work is applicable to the rosin powder adhesive material? how to use?
A: Rosin powder is suitable for binding hot stamping. When the surface of the material to be heated has micropores and the hot material cannot be bonded, the rosin powder may be spread on the surface of the material to be heated, so that the powder penetrates into the micropores sufficiently, and the rosin powder is melted under the conditions of heat and pressure to be hot. The material adheres to the surface of the object to be heated. Rosin powder is the best adhesive material for hot stamping red gold and silver foil.
There are two methods of use: one is to coat with cotton dust; the other is to use a mesh tool to spread.

495. What should I pay attention to when using rosin powder?
Answer: It should be noted that: (1) Rosin powder is only suitable for hot stamping on the surface of materials with microporous fabrics, etc., because the fabric surface has fibrous pores, powdery sticky

The material can be applied to the fabric and penetrated into the fabric. After being hot pressed, it has a good adhesive effect. (2) The rosin powder is not suitable for painting on smooth materials such as lacquer, leather and PVC (without pores on the surface) because the powder itself There is sliding, coated on the smooth body due to shaking during operation, so that the coated powder moves or off, affecting the hot stamping effect; (3) The use of rosin powder is a kind of auxiliary material, can not be used when not in use, must Apply less and evenly.

496. What is shellac?
A: Shellac, also known as shellac, dry paint and so on. The main component is the ester of the light-emitting acid, which is a brown micro-transparent body that is insoluble in water, soluble in alcohol and alkaline solutions, and slightly soluble in esters and hydrocarbons. Shellac is soft, softened by heat, and decomposed at high temperatures.

497. What kind of work is used to bind the shellac?
Answer: Since shellac has a certain adhesive strength, it is a good bonding material for hot stamping and processing. It is particularly suitable for hot stamping of red gold and silver foil on smooth bodies and adhesion of other hot materials. At the same time, the alcohol in the shellac is coated on the surface of the smooth hot stamping object, and it can also be dirty.

498. How to make shellac a liquid binder?
A: When shellac is purchased, it is a hard block (solid state). The first use of shellac is to be immersed in a liquid state. The method is: first crushed the large shellac into small pieces and put it into a glass container (the bottle can also be). The appropriate amount of alcohol was added to soak, and the container was sealed. After 10 hours, the shellac was dissolved by alcohol into a liquid binder with a certain concentration. The ratio of alcohol to shellac is about 200 grams of shellac per 500 grams of alcohol.

499. How to use shellac adhesive?
Answer: (1) After shellac is soaked for 10 hours, it can be used as a liquid binder, and it should be shaken or stirred evenly before use. (2) When used, apply a cotton swab to apply on the location where hot stamping is needed; (3) Shellac is liquid and microscopic when used

It is slightly brown and can only be used to smooth the surface of the body, such as lacquer, leather, PVC and other materials. Do not use on fabrics, papers, etc., because the brown shellac liquid will penetrate into the gaps on the surfaces of the porous objects, causing the hot objects to change color or have brown glue marks, causing the surface to be dirty.

500. What is a casein adhesive?
Casein is another kind of proteinaceous binding agent. It is produced by acidification and degreasing, so it has better dissolution performance. Casein is swelled after absorbing water, and it is easily dissolved in an alkaline solution to form a viscous liquid binder.

501. How to make casein binder?
In the production process, the casein is first soaked in water to make it swell, and then some weakly alkaline additives are added to make it easy to dissolve. Then it is heated and stirred to make a 25% solution. The alkaline additive can be borax, ammonia, sodium hydroxide and phosphorus. Or alkaline substances such as sodium carbonate. The borax is weak and stable, and the ammonia easily evaporates when the casein forms a film, so it is better to use these two substances.
Since alkaline additives are added to casein, they should be prepared using containers that are not attacked by alkali. Do not use containers such as copper or aluminum. Casein protein prone to bacterial deterioration, need to add an appropriate amount of preservatives, in order to facilitate the delay of preservation time.

502. What is cellulosic adhesive material? Which kind?
A: Cellulosic adhesive materials consist essentially of cellulose-modified solutions, such as paper, paper, and other basic materials. There are two types, one is carboxymethyl cellulose and the other is methyl cellulose.

503. What is carboxymethyl cellulose cement?
A: Carboxymethyl cellulose is an ether of cellulose and glycolic acid, also known as paper frizz. The binder material is first crushed paper, chemically alkalized, etherified to make carboxymethyl cellulose, and then processed by neutralization. This material can be purchased from outside or made by yourself.

504. How to make carboxymethyl cellulose adhesive material?

A: The production methods and ingredients are shown in Table 1.
Stir with boiling water, add flavor and phenol, and continue stirring until it becomes a bondable material.

505. What are the characteristics of carboxymethyl cellulose adhesive materials?
A: The viscosity and strength of carboxymethylcellulose adhesive after drying is better than that of flour paste. The elasticity of the film is good, colorless and transparent, and it is not afraid of biting by insects, deterioration, non-precipitation, long storage time; its viscosity can be Free water modulation, and can be mixed with flour paste, polyvinyl acetate, etc., can get better results.
The carboxymethyl cellulose binder has a slower drying speed and lacks cohesive force at the beginning. As the moisture evaporating adhesive strength gradually increases, the adhesive strength is good after being completely dried.

506. What is methyl cellulose cement?
A: Methyl cellulose is an ether of cellulose and methanol. The colloid is a white or beige sheet that dissolves in cold water. The surface tension decreases when dissolved. The glue will condense at 50°C, and will recover after cooling. The original dissolved body. Non-toxic, high resistance to bacteria, and very stable to ultraviolet light.

507. How to use methyl cellulose?
A: It can be used after purchase. It is used for binding covers, sheets, etc. The glue is easy to apply, but sometimes it is a bubble, and an appropriate amount of tributyl phosphate can be added to prevent the effect of bubbles on coating adhesion.

508. What is a synthetic resin adhesive material?
A: Synthetic resins, also known as synthetic resins and artificial synthetic resins, are resins made by polymerizing or polycondensing monomer resins. Synthetic resin adhesive material is a kind of adhesive material with a wide range of materials, easy to use, and a wide variety of materials. A variety of such adhesive materials are often used in post-press processing.

509. What are the types of synthetic resin binder used in postpress processing?
A: There are polyvinyl acetate (PVAC), polyvinyl alcohol (PVA), polyvinyl formal (107 gel), ethylene vinyl acetate (VAE), ethylene vinyl acetate copolymer hot melt adhesive (EVA), acrylic Ester - vinyl acetate (504) adhesive, polypropylene-based paper plastic composite adhesive, polyurethane (PUR) adhesive and many other.

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