Hot Stamping Technology--Types of Hot Stamping Materials (5)

3. Color hot stamping material.

The color film is a kind of hot stamping material that is coated on paper and other flat and smooth objects by depositing a layer of mixed paint such as a pigment and a binding material, and drying and peeling off the paper.

The production of color chips has a history of nearly 60 years and is manual operation. The color film is dedicated to hot stamping bookcases. In the absence of color foils, glue is used to stamp various colored prints with this material. The feature of the color film is that it is simple and easy to process, the color is bright, and the hot and thick traces are pure and pure. However, the color film has no support body and it is easy to be broken and difficult to preserve. The use of color tablets for hot stamping has good results. Some high-end books with multi-color designs use hot stamps for hot stamping. The main reason is that the colors reflect the truth, and they are not easy to reflect and easy to read after encountering light.

(1) Production of color chips. The production of color chips is done manually and is divided into three steps.

1 Select the paint deposition plate. To make a color chip, you must first select and prepare a flat, smooth surface plate (usually 400mm x 200mm or 600mm x 300mm) of glass, and check whether there are blisters, etc., then wash it with clean water, dry it, and wait. . The surface of the coated plate must not contain dust, fiber wool, and other contaminants.

2 mix color paste. The main raw materials for the color pastes of color chips are: Colors—including various kinds of required light colorants and matte color materials; the main function is to present colors; adhesive—resin, shellac, or rosin Etc., the main role is to bond the color and the weak connection with the material to be heated; filler - titanium dioxide (appropriate use); solvent - industrial alcohol wax (can be used), the main role is to make the color film easy to dry Plates are peeled off.

Prepare a variety of adhesive material, and prepare it for uniform use. Dilution of color paste should be appropriate, not too thick, excessive waste of raw materials, increase costs, and difficult to process; not too thin, thinning will make the color layer thin, not reflect the hue of the color itself. The proportion of pigments and adhesives should be appropriate. Adhesive materials are too easy to change color, easy to peel, too few color chips after drying are easy to break, and not hot stamping. The degree of dilute thickness should be such that it can not only be firmly stamped, but also not easily peeled off and not broken.

3 deposition coating color paste. After the plates, color pastes, and the like have been prepared, deposition of the color chips can be performed. Before coating, a layer of wax can be applied on the plate to make it easier to separate (it can also be separated without applying wax liquid, but the effect is not as good as wax coating). Coating is generally performed by hand. The method is:

a. The cleaned plate (waxed or unwaxed) is placed on a flat table, and the adjusted color paste is evenly poured or coated on the plate for uniform deposition and coating.

b. The deposited color paste is compatible with the area of ​​the plate and the thickness of the coating, and the general thickness is approximately 0.3 mm.

c. After the coating is deposited, lay it flat and dry. After it is completely dry, peel it off and place it on the previously prepared paper. Place a layer of paper on each color sheet (the size of the pad is the same as the color film), complete the color film. Production processing.

(2) Packaging of color chips. After the color film is made, because no support is easy to break, it needs to be stored in flat carton when packing. Each box has a specified quantity (the size of the box is slightly larger than the color film 10-20mm), and then it is boxed. big package. Standardize the color and processing date on the surface of each flat box and each large carton to facilitate user selection.

(3) Hot stamping. The colors of the color film are numerous and can be arbitrarily produced and selected according to the needs. However, the quality and color of the finished products vary depending on the manufacturing process and the amount of materials used. The color film is mainly used for the hot stamping of the book case, which directly affects the appearance quality. Therefore, the performance of the color film must be mastered during the hot stamping process. The color film is different from the color foil and the electro-aluminum foil. It has no support body and is in the form of a piece. It cannot be used for automatic continuous hot stamping operation. Hot stamping processing should generally note the following points:

1 According to the size of the hot area, the color film will be cut into the appropriate specifications, and should be lightly placed to avoid the broken color chips.

2 When the hot stamping, the good color film will be placed on the hot surface of the hot stamping press, hot after the excess color film repair, make the imprint clear and clean.

3 In the case of normal pressure, time, and temperature, if hot stamping is not possible, sticking aids should be added to overcome the defects that the hot-plate adhesive force is poor and hot or hot.

After the 4-color hot stamping, the color should be bright, the color quality is good, firm, and the quality problems such as the unblemished version and the hair-flowering.

5 Stamping temperature Please refer to Table 2-6. The stamping pressure should be slightly larger than that of stamping anodized aluminum and color foil.

4. Metal foil stamping material. The metal foil is a thin metal sheet that is expanded with metal or made of metal powder. The use of metal foil binding books has been in China for centuries. At the end of the 15th century, books were decorated with red gold foil, and more and more metal foils were used to stamp the covers.

There are several kinds of metal foils: red gold foil, silver foil, copper foil and aluminum foil. Among them, the use of red gold foil is the most common and the time of use is longest. Until now, there are some valuable valuable books that are still stamped with red gold foil, but the general publications The gold of this book is replaced by anodized aluminum.

(1) Red gold foil and its hot stamping process. Red gold foil is an extremely thin foil stamping material that is extended with pure gold and fillers. The appearance of the red gold is very gorgeous, soft texture, chemical stability, not easy to oxidize and lose luster, and the extension performance is the best kind of metal. The thickness of the red gold foil used in hot stamping is only about 1 μm. Gold foil is made by tapping and rolling. Its packaging method is a layer of gold foil, a burr paper, and then loaded into the carton, and then carry out large packages.

The use of red gold foil for hot stamping is difficult and requires a certain amount of operating skills and experience. Hot stamping red gold foil is as follows:

1 First, the red gold foil together with the pad paper, according to the size of the hot-stamped area, cut into the appropriate size, into the carton to be used.

2 shop gold operation. The gold foil is thin and light, once encountering the air flow (larger breathing, words may cause the gold foil to be wasted), the gold foil will curl into a mass and cannot be laid on the plate and flow out, so pay special attention to the gold plating.

The sequence of operation for gold plating is: a. The upper stamping is heated to a certain temperature and the layout is face up; b. The book envelope coated with the adhesion aid is placed in the rules; c. The red gold foil is placed on the hot stamping In the above edition, the gold hand grips a ball of cotton on the left hand, and the right hand takes the medical forceps to gently open the burrs on the gold foil and throw it away. Then the gold foil is clamped together with a piece of paper under the gold foil and accurately laid on it. Stamping; d. After the gold foil is covered with a left-handed cotton group, the gold foil is compacted, and it is firmly attached to the hot stamping to complete the gold plating operation.

3 stamping hot stamping are all active, that stamping can pull, turn one. During the operation, the iron foil on the paved gold foil is turned one by one and the layout is face down and put into the upper groove of the hot stamping machine. After pressing, the gold foil is stamped and burned on the cover of the book cover which is placed in advance, and the hot gold foil is finished. The operation of processing. See Table 2-6 for time and temperature of hot red gold foil.

4 After ironing, remove the excess red gold leaf on the book case. When cleaning, use a bamboo or gauze to lightly blot around, so that the imprinting is clear and clean, but the imprint cannot be scratched.

The key to the operation of hot red gold is to shop gold foil, save a good shop and save money, and the high efficiency of the shop will cause great waste. Therefore, the gold plating operation has the following requirements: First, when gold foil is covered, the gold foil must be accurately lifted, and the gold foil that is caught must be accurately laid on the hot point along with the airflow. Avoid curling on the way. If there is a gold foil defect or halfway Broken, wrinkled damage, can not be covered when full coverage, it is necessary to make up a timely repair to prevent missed missed hot. The second is that the gold foil on the iron plate should be promptly pressed with the cotton ball firmly according to the actual situation, so as to avoid the gold foil falling off during the reprinting, resulting in waste. Third, due to improper gold plating operations and other reasons cause gold foil curl, wrinkle damage can not be hot stamping, it should be promptly stored in the carton, gold foil is a precious metal, can not be thrown to cause waste.

Covers stamped with red gold foil can be stored for long periods of time, but match the cover material. In China and other countries, books with high conservation value still use red gold foil as hot stamp material.

(2) Pure silver foil and its hot stamping process. Pure silver foil is a hot stamping material that is extended into foil by pure silver. Silver soft stretchability is second only to red gold, so pure silver foil is slightly thicker than bare gold foil. Silver is gorgeous and has stable chemical properties and should be preserved for a long time. However, the price is much cheaper than gold and it is a valuable material. Prior to the absence of electro-aluminum foil, silver prints were stamped with silver foil.

Silver foil processing, packaging, hot stamping process and red gold foil is basically the same, but thicker silver foil, hot stamping is more convenient than the red gold foil. The history of the use of silver foil is also very long, but the amount of use is very small, because the general preservation of the books are decorated with gold-based, silver shop.

(3) Copper foil and hot stamping process. On transparent paper substrates that have been infiltrated with resin or wax materials, sheets made of paint and coated copper powder are called copper foils. After the copper foil is made of gold, it looks like gold, so it is also called false gold or fake gold. Copper is easily oxidized in the air and turns dark brown, and the images after hot stamping are not durable. Copper foil is thicker than gold and silver foils, and its thickness is generally about 0.3mm. When hot stamping copper foil, the copper powder of the copper foil is adhered on the resin glue (or shellac) layer spread on the paper base. When the sticky copper is sticky, it will separate out, sometimes it will fall off after being hot. Powder and other phenomena.

In the absence of electro-aluminum foil, the use of copper foil is the same as the use of gold foil in hot stamping.

(4) aluminum foil and its hot stamping process. Aluminum foil is a hot stamping material that is directly calendered into a sheet using metallic aluminum. In the absence of electro-aluminum foil, in addition to using silver hot silver, there are silvery white luster, if the aluminum rolled sheet, with silicon silicate and other materials paste on the offset paper, made of aluminum foil, but also in the above Printing inks, used as a variety of high-grade wrapping paper. The aluminum foil itself is prone to oxidized color darkening, friction touch will fade, so it should not be used in the long-term preservation of the cover of the books. The method and requirements for hot stamping of aluminum foil are basically the same as those of copper foil.