What do you know about printing inks?

Ink is a homogeneous mixture composed of colored bodies (such as pigments, dyes, etc.), binders, fillers (fillers), additives and other substances; Able to print and dry on the printed body; It is a slurry adhesive with color and a certain degree of fluidity. Therefore, color (hue), body bone (rheological properties such as thinness and fluidity) and drying properties are the three most important properties of inks. There are many types of them, and their physical properties are also different, some are very thick and sticky; And some are quite thin.

Some use vegetable oil as the binding material; Some use resin, solvent or water as binders. These are determined according to the object of printing, i.e., the substrate, the printing method, the type of printing plate and the drying method.

With the development of printing technology, the variety of ink is increasing, pigment is a solid component in ink, is the chromogenic substance of ink, generally insoluble pigment in water. The saturation, tinting strength, transparency and other properties of the ink color are closely related to the performance of the pigment. The binder is the liquid component of the ink, and the pigment is the carrier.

In the printing process, the binder carries the pigment particles, which are transferred from the ink half of the printing press to the substrate through the ink roller, the printing plate, and the substrate to form an ink film, which is fixed, dried and adhered to the substrate. The gloss, dryness, mechanical strength and other properties of the ink film are related to the properties of the binder. The additives added to the ink are to improve the printability of the ink, such as:

Viscosity, adhesion, dryness, etc. There are also many ways to classify them. If it is classified according to the printing method, there are five types:

printing inks; printing inks; Letterpress printing ink: black ink for books, rotary black ink, color letterpress ink, etc.; Lithographic inks: offset bright resin inks, offset rotary inks, etc.; Gravure printing inks:

photogravure ink, engraving gravure ink, etc.; Stencil printing inks: transcription inks, screen inks, etc.; Special printing inks: foaming inks, magnetic inks, fluorescent inks, conductive inks, etc.

There are many types of inks, with different physical properties, some are very thick, some are very sticky, and some are quite thin. Its composition can be divided into three parts: the liquid component is called the connecting material; Solid components are called pigments (pigments or dyes) as well as various additives.

Different inks are dried in different ways: different inks are used in different printing processes; Different substrates use different inks. According to different drying methods, it can be divided into:

Oxidation condensation film drying ink, penetration drying ink, volatile drying ink, radiation drying ink, wet solidification drying ink, condensation drying ink, precipitation drying ink, two-component reaction drying ink, gelatinization drying ink, filter drying ink, dry ink combining multiple methods.

Printing ink is divided into 6 categories, which can be classified according to the plate classification, substrate classification, printing machine classification, color efficiency classification, special printing use classification, ink dryness classification, classification as follows: according to the plate classification, divided into lithographic, gravure, letterpress, flexographic, screen ink. According to the classification of substrates, it is divided into paper, film, metal, glass, ceramics, leather and textiles.

According to the classification of printing models, it is divided into rotary presses, flatbed machines, screen printing machines, flexo printing machines, gravure printing machines, and embossing machine inks. According to the classification of color performance, it is divided into chromatic ink, ordinary color, fast-drying bright type, UV type, UV hybrid ink, etc. According to the classification of special printing purposes, it is divided into thermal, optical, conductive, magnetic, foaming, and anti-counterfeiting inks.

According to the classification of ink dryness, it is classified as oxidizing conjunctival type, volatile type, permeable type, thermosetting type, cold setting type, light setting type, wet setting type, microwave type, electron beam ink, etc.

Printing inks are:

1. Letterpress ink. A type of ink that prints periodicals, magazines, newspapers, brochures, bills, account books, etc. by letterpress printing method. The key feature of letterpress printing is that the printing plate is stained with ink, and the part is raised from the non-ink.

According to the type of printing machine and the main use of printing products, letterpress ink is divided into lead printing ink, coated paper ink, letterpress rotation ink, and flexible letterpress ink.

2. Lithography ink. A type of ink suitable for lithographic printing. Most of the parts of the lithography are in a plane plan, the pattern is oil-friendly, the non-pattern is hydrophilic, and the basic principle of water and oil repulsion is used to carry out printing, so the lithographic ink must have waterproof characteristics.

According to the processing technology, it is divided into offset printing ink, roll offset printing ink, flat offset printing ink, waterless offset printing ink, printing iron ink, lithographic ink, and Koro ink.

3. Gravure printing ink. A type of ink that can be printed with gravure printing. During printing, the part of the pattern that is recessed in the layout is inked, and the ink of the non-pattern part is wiped off or scraped, and then the printing is started. There are hand-engraved gravure printing inks and photographic gravure printing inks.

4. Mesh ink. A type of ink that prints on the surface of the printing process according to the mesh leakage of the printing plate. Mesh inks are further divided into transcription inks and wire mesh inks.

According to the nature of ink, it is mainly divided into two types: solvent-based ink and water-based ink, one is insoluble in water, and the other is soluble in water.

According to the printing method, it is divided into: flat ink, gravure ink, letterpress ink, orifice plate ink, and special ink.

According to the ink effect: ordinary ink, fluorescent ink, color-changing ink, mirror ink, fragrance ink, scratch card ink, laser ink, magnetic ink, anti-counterfeiting ink.

According to the ink drying method: hot drying ink, UV drying ink, EB drying ink and so on.

According to the composition of the connecting material, it can be divided into oxidized conjunctival drying resin materials, volatile drying solvent inks, two-component reactive inks and ultraviolet curing inks.

Classified by printing material: paper ink, plastic ink, printing iron ink, glass ink, ceramic ink, ......There are many ways to classify them.

The main types of printing inks are: lithographic (offset) ink, gravure ink, embossing ink, silk screen printing ink and other four categories; Lithographic (offset) ink is divided into sheet-fed paper ink and rotary machine ink according to the model, and is divided into printing paper ink, iron printing ink, synthetic paper ink, UV offset printing ink, gold and silver ink, fluorescent ink, cold-setting rotary ink, thermosetting rotary ink and UV rotary ink; Gravure inks and embossing inks are not only solvent inks and water-based inks, but also plastic inks and printing paper inks; There are more screen printing inks according to types, including printing paper inks, hard plastic inks, soft plastic inks, metal inks, solvent inks, UV inks, etc.

1.Letterpress ink: a type of ink that prints books, newspapers, albums, documents, account books, etc.

The main feature of letterpress printing is that the inking part of the printing layout is protruding from the non-inking part. According to the type of printing machine and the use of printed products, letterpress ink is divided into lead printing ink, copperplate ink, letterpress rotary ink, and flexographic letterpress ink.

2.Lithography ink: a class of inks suitable for lithographic printing.

The layout of lithography is basically in a plane, the pattern is oil-friendly, the non-pattern is hydrophilic, and the principle of oil and water repulsion is used for printing, so the lithographic ink must have water resistance. According to the process, it is divided into offset printing ink, web offset printing ink, flat offset printing ink, anhydrous offset printing ink, printing iron ink, lithographic ink, and Koro ink.

3.Gravure ink: a type of ink suitable for gravure printing. During printing, the pattern part that is recessed in the layout is inked, and the ink on the non-pattern part is wiped off or scraped, and then printed. There are engraving gravure inks and photogravure inks.

4.Mesh ink: A type of ink that prints through the mesh of the printing plate to the substrate surface. Mesh inks are further divided into transcription inks and screen inks.

1.What is ink?

Printed materials composed of pigments, binders, fillers, additives, etc.

2.What is the classification of inks?

1) According to the printing method.

According to the layout, it is divided into: letterpress, lithograph, gravure, photogravure, screen and other inks;

According to the printing method, it is divided into: offset printing, direct printing and other inks.

2) According to the substrate of the substrate.

According to the substrate, it is divided into: inks for paper, metal, plastics, fabrics, etc.

3) According to the dry form.

According to the drying mechanism, it is divided into: permeation drying type, oxidation polymerization type, volatile drying type, light hardening type, thermosetting type, cooling curing type and other inks;

According to the drying method, it is divided into: natural drying type, hot air drying type, infrared drying type, ultraviolet drying type, cooling drying type and so on.

4) According to the characteristics of the ink.

According to the color: yellow, red, blue, white, black, gold, silver, gold powder, fluorescent, pearlescent, etc.;

According to the function, it is divided into: magnetic ink, anti-counterfeiting ink, edible ink, foaming ink, aromatic ink, recording ink, etc.;

According to the resistance, there are: light resistance, heat resistance, solvent resistance, abrasion resistance, alcohol resistance, chemical resistance and other inks.

5) According to the composition of the ink.

According to the raw materials, there are: dry oil type, resin oil type, organic solvent type, water-based type, paraffin type, ethylene glycol type and other inks;

According to the form, it is divided into: gelatinous, liquid, and powdery inks.

According to the use, it is divided into: news ink, book ink, packaging ink, building materials ink, trademark ink, etc.

3.How do I use the ink?

In order to adapt to the printing of high-quality paper at high speed, the penetration drying type or oxidation conjunctival drying type can no longer meet the requirements, and it is easy to produce poor dryness, poor adhesion, pulverization, rubbing, etc., in order to overcome these drawbacks, the use of thermosetting ink, that is, in printing, after 200 250 high temperature baking, the solution in the ink escapes, so that the ink is fixed on the printed matter.

There are two main types of ink properties: solvent-based inks and water-based inks, one is insoluble in water and the other is soluble in water.

Printing methods are divided into: flat ink, gravure ink, letterpress ink, orifice plate ink, special ink.

Ink Effect: Ordinary Ink, Fluorescent Ink, Color Changing Ink, Mirror Ink, Fragrance Ink, Scratch Card Ink, Laser Ink, Magnetic Ink, Anti-counterfeiting Ink.

Ink drying method: hot drying ink, UV drying ink, EB drying ink and so on.

The composition of the binder can be divided into oxidized condensation film drying resin materials, volatile drying solvent inks, two-component reactive inks and ultraviolet curing inks.

Printing material classification: paper ink, plastic ink, printing iron ink, glass ink, ceramic ink, ......Wait.

UV ink is one of the indispensable conditions for UV printer printing, and it is a way to identify which is the right UV ink for your printer

The color of the ink.

UV ink is extremely sensitive to ultraviolet light, if UV ink is exposed to ultraviolet light for a long time, UV ink will change yellowing, which is a shortcoming of UV ink itself, and it is also a method that we can use to distinguish UV ink.

The smell of the ink.

To identify the quality of UV ink, it is necessary to start from its own taste, the smell in UV ink comes from the residual solvent contained in UV ink, under normal circumstances, the amount of residual solvent is less than 2%, which is also a point for everyone to distinguish UV ink; There is also a residual smell on the material for a long time after printing, if there is still a residual odor after a period of time, then it means that the quality of UV ink is not up to par caused by the formation of odor.

3.Drying time.

If you find that UV ink is difficult to cure when printing, then part of the reason appears on UV ink, so when you buy UV ink, you should pay attention to the quality of UV ink, which will not only affect the printing effect, but also bring different degrees of damage to the UV printer itself.

Hue, which is the basic characteristic of color, is used for qualitative distinction. When matching colors, the first thing to consider is whether the hue is consistent, and the detection method is usually to scrape the color on the sample paper or simulate printing, and observe and compare the standard sample and the sample with human eyes.

Hiding power, which is the degree to which the ink covers its base color. The better the opacity, the worse the transparency, which affects the efficiency of the ink color registration and the degree of influence of the printing substrate.

Tinting strength, tinting strength is a way to indicate the high and low density of ink. The determination is based on a certain amount of ink, then add a certain amount of standard white ink to dilute and mix, and then compare with the standard sample. The strength of the poor color strength reflects the degree of color mixing of the ink, which affects the thickness of the printing ink film.

Gloss, which can be measured with an instrument or judged by the naked eye, is usually observed only by the naked eye during the color matching process. Gloss actually refers to the degree of the ability of an ink printing sample to reflect light in the same direction after being exposed to light. It directly affects the appearance of the printed matter and is a very important indicator.

At the same time, when choosing ink, it is necessary to distinguish whether the ink itself is a glossy, semi-glossy or matte ink to avoid mixing errors.

Whether the ink is selected correctly depends on what substrate needs to be printed? What is the test standard, but now the environmental protection requirements, basically choose water-based printing ink, you can refer to:

For textile fabrics, the selection of water-based printing paste for priming, water-based three-dimensional paste, the selection of water-based cover paste for covering, water-based varnish paste, water-based varnish, water-based ink, water-based elastic ink, water-based ink, etc.

For rubber and plastics, there are water-based plastic inks, water-based rubber inks, water-based TPU inks, water-based ABS inks, water-based PVC inks, water-based varnishes, etc.

For metal materials, there are water-based printing inks, water-based self-drying inks, etc.

For leather, there are water-based printing inks, leather finishing agents, etc.

In fact, according to different materials and printing methods, there are many different products, such as flexographic printing ink, gravure printing ink, surface ink, lining printing ink and so on.