Flexo printing originated in the United States in the 1920s. Due to the toxicity of the aniline dye inks used, flexographic printing, originally called flexographic printing, has not been developed. In the 1970s, due to the advancement of industry, the development of high-polymer resin plates, ceramic anilox rollers, flexo printing inks, and UV drying technologies in recent years has led to a qualitative leap in the development of modern flexographic technology.
At present, the flexo process is the fastest growing printing process in the world. In terms of the label industry, the US flexo printing accounts for about 85% of the label industry; the European flexo printing started later than the United States, and the current market share is about It's 45%, and it's rising rapidly. Flexo printing is currently in its infancy in Asia and many manufacturers are launching new flexo presses. The development of flexographic printing technology is still in the ascendant. This was fully reflected in Chicago in the United States in 2000. All exhibitors have recently launched the latest flexographic or UV flexographic technology and equipment. Even some well-known equipment suppliers, formerly directed at the adhesive label industry's main software for the sudden printing of printed materials, quietly turned to the flexo version at the 2000 Chicago show, especially the UV flexo version. With the continuous progress of science and technology, flexo printing has gradually entered a new era. The flexographic printing industry has achieved great development thanks to its economy and high quality.
Avery Dennison began to get involved in flexo printing very early and began manufacturing its own UV flexo presses as early as fifteen years ago. At the same time, we also have a strong team of technical supporters, and gained a lot of experience in the accumulation of practice over the years. The following are some of the major factors that we believe will affect the quality of self-adhesive printing processes for readers' reference.
1. Separation film color separation film directly affects the quality and printing results. Since the flexographic printing uses mesh spinning rolls, the anilox roll meshes are arranged at a certain angle (currently 60 degrees or 45 degrees at most), and in order to avoid electroprinting, the flexographic film screening angle is 7.5 degrees compared to offset printing. The difference. If the film is used with a flat exposure system, the graphics should be compressed according to the diameter of the plate cylinder, the thickness and thickness of the double-sided adhesive before the film is formed. It should also pay attention to the performance of the film and media graphics performance match. The use of frosted film will be more conducive to the production of printing plates.
2. Plate material and production should first select the appropriate plate according to the type of ink used. Not all plates are suitable for using UV ink. Selection errors will cause the plate to swell and deform during printing. The plate making process is also very important, and the time control of each step should be just right. Underexposure, excessive de-sticking, insufficient drying, and improper storage will reduce the plate life.
3. The characteristics of the anilox roller First of all, the choice of roller should follow the following principles: The number of screens (line/inch or line/meter) of the separation film should be at least 1:3.5 with the anilox roller, dot printing should reach 1 : 5 ratio. The degree of cleaning of the anilox roller is also very important. Regular and thorough cleaning of the texture can ensure the ink transfer amount, ink color matching and repeat repeatability.
4. Ink type and compatibility, ink system Different substrates should use the corresponding ink system, such as paper ink, PE, PP, PET and other plastic film ink, PVC ink, aluminum foil ink and so on. Incorrect selection of the ink system, or poor ink compatibility, will lead to a decline in the performance and strength of the ink on the surface of the substrate, and may even cause a chemical reaction.
5. The corona treatment, surface coating, and UV lamp also affect the adhesion of the ink. The printability of the plastic film can be improved by the corona treatment of the printing surface and the application of a surface coating layer. The surface is coated with a variety of chemicals: acrylic, vinyl, etc., solvent-based or water-based. The use of gravure wheel or flexo printing, the advantage is: for printing no time limit, good wetting and ink binding force, suitable for most of the current market and ink, do not need online equipment and processing, chemical resistance And scratch better, suitable for printing at the same speed. The disadvantages are that the cost is more expensive than corona-treated material relative to the finished product, and corona treatment is the most common method currently used to improve the surface coatability, wettability, and adhesion of the PE/PP. The corona discharge is completed between the electrodes at the short distance. One end of the two electrodes is connected to a high frequency and high voltage, and the end of the array is grounded. For example, the corona treatment frequency range of a typical narrow web press is between 9-30 KHz, and the output is squeezing - 15,000 volts. In the case of large print speeds and high speeds, higher voltages are required. In corona discharge treatment, the discharge process releases electrons, ions, and protons contained therein, some of which impinge on the surface of the polymer and add to the free proton reaction sequence. The functional groups can be introduced on the surface. Most of these functional groups contain carbon and oxygen. Usually, the surface and force of the film after corona should reach 40 dyne or more will not cause the ink to fall off.
6. Ink color matching The color of the ink directly affects the color quality of the printed product, especially for spot color inks, which are usually first modulated in the ink chamber and detected using a colorimeter. The naked eye can no longer see the discernment, and factories that require more extensive use sometimes require it. The color density meter of a professional supplier is now more complete, and the instrument can provide recommended ink color formulae while measuring the sample according to the ink database provided by the ink manufacturer, which greatly improves work efficiency.
7. The printing press, its operation, and adjustment factors clearly determine the quality of the print. For example, the gear bar in flexo printing (which is the periodic bar formed by a gear in the printing unit drive system stuck on the print) is due to printing. The defects of the machine itself affect the quality of the printed product. The tension control ability and manufacturing accuracy of the printing press also affect the registration and printing accuracy.
8. Die-cutting is a feature of self-adhesive label printing. Label die-cutting has always been a significant component. The quality of die-cutting processes directly affects the labeling and use of labels. At present, the common die-cutting methods are round-pressing rounding and production flattening. The flat-pressing flat die-cutting speed is slow and the precision is slightly poor, while the round-pressing round die-cutting is not only fast and accurate, but also the machine adjustment loss is very small. . At present, the labeling of the product has been more and more using the automatic labeling method, and the labeling speed has become more and more reminiscent. Now, the speed of 250-300 Label/Min is not uncommon for medium and small labels. Therefore, the high-quality die-cutting processing of China's adhesives has become the market's development needs. At present, more and more various types of round-circular die cutters are seen as a product of the times. The medium-circle solid round die cutter has long service life, high die-cutting precision and fast operation, and is suitable for medium and long-lived work. However, the thin-plate round die-cutting die cutter used with the magnetic drum has a slightly shorter service life than the one-piece type. Die cutter, but die-cutting accuracy, running speed is also excellent, suitable for short-lived version. Moreover, round-circular die cutters have been steadily declining in prices in Europe and the United States in the past decade, and so far they have dropped by 30-50%. The development of die-cutting knives is a great impetus for the flexographic printing of adhesive labels, including flexographic printing.
9. Static electricity and static electricity are often overlooked, but static electricity is often a very important factor in actual production. Electrostatic charges are formed by friction and induction and are more pronounced on the film. Therefore, the entire adhesive manufacturing and printing process will generate electrostatic charges that will occur on the materials and the machine. If they are not removed in time, they will cause a lot of troubles and quality problems with the adhesive tape. Problems that may be caused by static electricity in label processing :
1) Print quality (all printing methods): The needles or nets are missing on the label, and each defect is caused by partial discharge of a certain amount of charge (which can be considered as a small explosion);
2) Ink build-up or repulsion: Static electricity on the material or machine can cause uneven distribution of the ink on the material, appearing to be deep and shallow;
3) Die-cutting/effluent quality; the label is discharged along with the waste, so operators often mistakenly believe that the pressure of the die-cutting knife is insufficient and apply more pressure to the die-cutting knife so that the hair-cutting tool is easily worn out. Or destroy it to reduce its service life.
4) Tension quality: When stripping and rewinding materials, excessive static electricity leads to uneven rewinding, causing gel penetration.
5) Laminating quality: Due to electrostatic attraction, the laminating layer is prematurely laminated, resulting in uneven laminating.
6) Labeling quality: When the label is labelled, the label is not normally issued, but it runs with the backing paper, which affects the labeling speed and quality.
7) Punching quality: After punching the label, the waste still stays on the paper.
8) Thermal transfer/laser print quality: Partially hit, partially hit, and print quality differ (deep or shallow).
9) Dust is sucked onto the substrate or printing plate, forming fisheye or white point defects on the printed product;
10) Electric shock operators or other employees: This kind of experience has been experienced by many rotary press operators, not only reducing the output and quality of the products, worsening the working conditions of the operators, and even causing serious accidents such as fires;
11) Solution to electrostatic problems:
(1) Sensing: Set the wire to remove or neutralize static electricity on the printing path. Simple, low cost but requires pre-installation. Electrostatic wires and machines must be properly grounded. Some printers connect the static-free wire to the frame of the machine cabinet, which often does not provide the best static removal effect. The charge will accumulate on the machine, which will also cause quality problems. The distance between the metal wire and the material is also very important. Generally, the wire does not directly touch the surface of the substrate. It is better to leave the wire slightly. If the material is thick, the double-sided removal effect is better. If the material is thick, double-sided removal Better results. However, it should be noted that when the double-sided removal is performed, the wires should not be symmetrically distributed in pairs, and staggered installation will have an increasing effect.
(2) Ionization: The use of a material that emits a large number of positive and negative ions. The charged material absorbs the required number of positive and negative ions according to neutralization requirements. This method requires specialized equipment, but the effect is ideal.
At present, the flexo process is the fastest growing printing process in the world. In terms of the label industry, the US flexo printing accounts for about 85% of the label industry; the European flexo printing started later than the United States, and the current market share is about It's 45%, and it's rising rapidly. Flexo printing is currently in its infancy in Asia and many manufacturers are launching new flexo presses. The development of flexographic printing technology is still in the ascendant. This was fully reflected in Chicago in the United States in 2000. All exhibitors have recently launched the latest flexographic or UV flexographic technology and equipment. Even some well-known equipment suppliers, formerly directed at the adhesive label industry's main software for the sudden printing of printed materials, quietly turned to the flexo version at the 2000 Chicago show, especially the UV flexo version. With the continuous progress of science and technology, flexo printing has gradually entered a new era. The flexographic printing industry has achieved great development thanks to its economy and high quality.
Avery Dennison began to get involved in flexo printing very early and began manufacturing its own UV flexo presses as early as fifteen years ago. At the same time, we also have a strong team of technical supporters, and gained a lot of experience in the accumulation of practice over the years. The following are some of the major factors that we believe will affect the quality of self-adhesive printing processes for readers' reference.
1. Separation film color separation film directly affects the quality and printing results. Since the flexographic printing uses mesh spinning rolls, the anilox roll meshes are arranged at a certain angle (currently 60 degrees or 45 degrees at most), and in order to avoid electroprinting, the flexographic film screening angle is 7.5 degrees compared to offset printing. The difference. If the film is used with a flat exposure system, the graphics should be compressed according to the diameter of the plate cylinder, the thickness and thickness of the double-sided adhesive before the film is formed. It should also pay attention to the performance of the film and media graphics performance match. The use of frosted film will be more conducive to the production of printing plates.
2. Plate material and production should first select the appropriate plate according to the type of ink used. Not all plates are suitable for using UV ink. Selection errors will cause the plate to swell and deform during printing. The plate making process is also very important, and the time control of each step should be just right. Underexposure, excessive de-sticking, insufficient drying, and improper storage will reduce the plate life.
3. The characteristics of the anilox roller First of all, the choice of roller should follow the following principles: The number of screens (line/inch or line/meter) of the separation film should be at least 1:3.5 with the anilox roller, dot printing should reach 1 : 5 ratio. The degree of cleaning of the anilox roller is also very important. Regular and thorough cleaning of the texture can ensure the ink transfer amount, ink color matching and repeat repeatability.
4. Ink type and compatibility, ink system Different substrates should use the corresponding ink system, such as paper ink, PE, PP, PET and other plastic film ink, PVC ink, aluminum foil ink and so on. Incorrect selection of the ink system, or poor ink compatibility, will lead to a decline in the performance and strength of the ink on the surface of the substrate, and may even cause a chemical reaction.
5. The corona treatment, surface coating, and UV lamp also affect the adhesion of the ink. The printability of the plastic film can be improved by the corona treatment of the printing surface and the application of a surface coating layer. The surface is coated with a variety of chemicals: acrylic, vinyl, etc., solvent-based or water-based. The use of gravure wheel or flexo printing, the advantage is: for printing no time limit, good wetting and ink binding force, suitable for most of the current market and ink, do not need online equipment and processing, chemical resistance And scratch better, suitable for printing at the same speed. The disadvantages are that the cost is more expensive than corona-treated material relative to the finished product, and corona treatment is the most common method currently used to improve the surface coatability, wettability, and adhesion of the PE/PP. The corona discharge is completed between the electrodes at the short distance. One end of the two electrodes is connected to a high frequency and high voltage, and the end of the array is grounded. For example, the corona treatment frequency range of a typical narrow web press is between 9-30 KHz, and the output is squeezing - 15,000 volts. In the case of large print speeds and high speeds, higher voltages are required. In corona discharge treatment, the discharge process releases electrons, ions, and protons contained therein, some of which impinge on the surface of the polymer and add to the free proton reaction sequence. The functional groups can be introduced on the surface. Most of these functional groups contain carbon and oxygen. Usually, the surface and force of the film after corona should reach 40 dyne or more will not cause the ink to fall off.
6. Ink color matching The color of the ink directly affects the color quality of the printed product, especially for spot color inks, which are usually first modulated in the ink chamber and detected using a colorimeter. The naked eye can no longer see the discernment, and factories that require more extensive use sometimes require it. The color density meter of a professional supplier is now more complete, and the instrument can provide recommended ink color formulae while measuring the sample according to the ink database provided by the ink manufacturer, which greatly improves work efficiency.
7. The printing press, its operation, and adjustment factors clearly determine the quality of the print. For example, the gear bar in flexo printing (which is the periodic bar formed by a gear in the printing unit drive system stuck on the print) is due to printing. The defects of the machine itself affect the quality of the printed product. The tension control ability and manufacturing accuracy of the printing press also affect the registration and printing accuracy.
8. Die-cutting is a feature of self-adhesive label printing. Label die-cutting has always been a significant component. The quality of die-cutting processes directly affects the labeling and use of labels. At present, the common die-cutting methods are round-pressing rounding and production flattening. The flat-pressing flat die-cutting speed is slow and the precision is slightly poor, while the round-pressing round die-cutting is not only fast and accurate, but also the machine adjustment loss is very small. . At present, the labeling of the product has been more and more using the automatic labeling method, and the labeling speed has become more and more reminiscent. Now, the speed of 250-300 Label/Min is not uncommon for medium and small labels. Therefore, the high-quality die-cutting processing of China's adhesives has become the market's development needs. At present, more and more various types of round-circular die cutters are seen as a product of the times. The medium-circle solid round die cutter has long service life, high die-cutting precision and fast operation, and is suitable for medium and long-lived work. However, the thin-plate round die-cutting die cutter used with the magnetic drum has a slightly shorter service life than the one-piece type. Die cutter, but die-cutting accuracy, running speed is also excellent, suitable for short-lived version. Moreover, round-circular die cutters have been steadily declining in prices in Europe and the United States in the past decade, and so far they have dropped by 30-50%. The development of die-cutting knives is a great impetus for the flexographic printing of adhesive labels, including flexographic printing.
9. Static electricity and static electricity are often overlooked, but static electricity is often a very important factor in actual production. Electrostatic charges are formed by friction and induction and are more pronounced on the film. Therefore, the entire adhesive manufacturing and printing process will generate electrostatic charges that will occur on the materials and the machine. If they are not removed in time, they will cause a lot of troubles and quality problems with the adhesive tape. Problems that may be caused by static electricity in label processing :
1) Print quality (all printing methods): The needles or nets are missing on the label, and each defect is caused by partial discharge of a certain amount of charge (which can be considered as a small explosion);
2) Ink build-up or repulsion: Static electricity on the material or machine can cause uneven distribution of the ink on the material, appearing to be deep and shallow;
3) Die-cutting/effluent quality; the label is discharged along with the waste, so operators often mistakenly believe that the pressure of the die-cutting knife is insufficient and apply more pressure to the die-cutting knife so that the hair-cutting tool is easily worn out. Or destroy it to reduce its service life.
4) Tension quality: When stripping and rewinding materials, excessive static electricity leads to uneven rewinding, causing gel penetration.
5) Laminating quality: Due to electrostatic attraction, the laminating layer is prematurely laminated, resulting in uneven laminating.
6) Labeling quality: When the label is labelled, the label is not normally issued, but it runs with the backing paper, which affects the labeling speed and quality.
7) Punching quality: After punching the label, the waste still stays on the paper.
8) Thermal transfer/laser print quality: Partially hit, partially hit, and print quality differ (deep or shallow).
9) Dust is sucked onto the substrate or printing plate, forming fisheye or white point defects on the printed product;
10) Electric shock operators or other employees: This kind of experience has been experienced by many rotary press operators, not only reducing the output and quality of the products, worsening the working conditions of the operators, and even causing serious accidents such as fires;
11) Solution to electrostatic problems:
(1) Sensing: Set the wire to remove or neutralize static electricity on the printing path. Simple, low cost but requires pre-installation. Electrostatic wires and machines must be properly grounded. Some printers connect the static-free wire to the frame of the machine cabinet, which often does not provide the best static removal effect. The charge will accumulate on the machine, which will also cause quality problems. The distance between the metal wire and the material is also very important. Generally, the wire does not directly touch the surface of the substrate. It is better to leave the wire slightly. If the material is thick, the double-sided removal effect is better. If the material is thick, double-sided removal Better results. However, it should be noted that when the double-sided removal is performed, the wires should not be symmetrically distributed in pairs, and staggered installation will have an increasing effect.
(2) Ionization: The use of a material that emits a large number of positive and negative ions. The charged material absorbs the required number of positive and negative ions according to neutralization requirements. This method requires specialized equipment, but the effect is ideal.
Dining Room Side Chairs,Leather Side Chairs,Upholstered Side Chair,Mid Century Side Chair
Foshan Misirui Furniture Co., Limited , https://www.misiruifurniture.com