introductory:
As a special printing ink, food-grade offset printing ink is mainly used in food packaging and other fields that are in direct or indirect contact with food. It is made of raw materials that meet food safety standards, and the content of harmful substances such as heavy metals and organic solvent residues is strictly controlled in the production process to ensure that it will not cause contamination to food. Compared with ordinary offset ink, it not only has higher safety and environmental protection, but also has good printability, can achieve clear and accurate pattern and text printing, rich and stable colors, moderate drying speed, the formed ink film has water resistance, friction resistance and other characteristics, which can ensure food safety at the same time, to meet the needs of food packaging in terms of appearance decoration and information transmission.
The following are the use and storage methods of food-grade offset printing inks:
How to use:
Preparation: Select the appropriate food-grade offset printing ink according to the printing task, and check whether the color and drying characteristics of the ink meet the requirements. At the same time, check whether the offset printing equipment is operating normally, including whether the ink roller, printing plate and other parts are clean and intact, and adjust the printing pressure and ink volume control device.
Ink addition: Open the ink barrel and stir the ink thoroughly with a special ink stirring rod to make it uniform. Then use an ink shovel or ink pump to add the ink to the ink fountain of the offset press, and the amount added should be reasonably controlled according to the printing task and the ink fountain capacity, so as to avoid too much or too little.
Printing commissioning: Before the formal printing, the trial printing is carried out. By adjusting the ink volume, printing speed, pressure and other parameters, observe the printing effect, such as whether the color is accurate, whether the ink layer thickness is uniform, whether there is dot deformation and other problems, until the satisfactory effect is achieved.
Formal printing: After the trial printing is qualified, the formal printing begins. During the printing process, it is necessary to continuously observe the printing quality and pay attention to the drying of the ink. If the ink dries too fast or too slowly, you can add an appropriate amount of desiccant or slow drying agent according to the characteristics of the ink. At the same time, it is necessary to regularly check the amount of ink in the ink fountain and replenish the ink in time to ensure the continuity of printing.
Equipment cleaning: After printing, the offset printing equipment should be cleaned immediately. Use a special ink cleaner to clean the residual ink on the ink roller, printing plate and other parts to prevent the ink from drying out and clogging the equipment and affecting the next use.
Storage:
Temperature control: food-grade offset printing ink should be stored in an environment with a temperature of 15°C-25°C, too high temperature may cause the ink to deteriorate and dry faster, and too low temperature may make the ink fluidity worse and caking.
Humidity management: the humidity of the storage environment should be kept between 40%-60%, too high humidity is easy to make the ink absorb water, affecting its performance, such as drying time extension, color change, etc.; Too low a humidity can cause the solvent in the ink to evaporate too quickly, making the ink thicker.
Keep away from light: The ink should be protected from direct sunlight and strong light, because light such as ultraviolet rays will accelerate the oxidation and drying process of the ink, and may also cause changes in the color of the ink, it is best to store the ink in a dark warehouse or storage cabinet.
Packaging sealing: The unused ink should ensure that the packaging is well sealed to prevent oxidation and crusting caused by excessive contact between the ink and air. The lid can be tightened after the mouth of the ink barrel is covered with a plastic film, or the ink package can be sealed using special sealing equipment.
Classified storage: Different types, colors and batches of food-grade offset printing inks should be stored separately to avoid confusion. At the same time, it should be stored separately from other chemicals to prevent mutual contamination or chemical reactions.
When using food-grade offset inks, there are the following precautions:
Ink selection
Compliance certifications: Ensure that the ink has passed food safety certifications, such as compliance with FDA (Food and Drug Administration), EU (European Union) Food Contact Material Regulation, etc., and request and view relevant test reports and certificates.
Scope of application matching: choose inks according to packaging materials and food types, such as paper packaging and plastic packaging have different adaptability to inks, and oil-containing foods, liquid foods, etc., need to choose inks with targeted resistance.
Printing operations
Equipment cleaning: Clean the offset printing equipment thoroughly before printing to avoid contamination of food-grade ink by impurities such as residual ink and dust, and maintain the equipment regularly to ensure that no mechanical wear and debris are mixed into the ink.
Environmental cleanliness: Keep the printing workshop clean and hygienic, the temperature is controlled at 18°C-25°C, the humidity is 40%-60%, reduce dust, microorganisms, and prevent ink from being polluted.
Operation specification: The operator wears clean work clothes, gloves, masks, etc., avoids skin contact with ink, controls the printing parameters according to the process requirements and operating procedures, and ensures the accuracy of ink dosage and drying time.
Quality inspection
Color detection: Use colorimeter and other tools to regularly detect the printing color, compare with the standard color sample, and adjust the ink formula or printing parameters in time when the deviation is out of range.
Adhesion test: The ink adhesion is tested through tests such as tape peeling to ensure that the ink does not fall off or transfer during the use of food packaging.
Dryness detection: Use a drying time tester to detect the dryness of the ink, incomplete drying will lead to ink transfer and adhesion, affecting the packaging quality and food safety.
Security protection
Ventilation measures: The printing workshop is equipped with good ventilation equipment to accelerate the discharge of volatile organic compounds in the ink and reduce the concentration of harmful gases.
Avoid accidental ingestion: The ink should be stored in a special area, away from food and food packaging materials, and be well marked to prevent misuse and ingestion.
Emergency treatment: Equipped with corresponding emergency treatment equipment and materials, such as adsorption materials, neutralizers, etc., in case of accidental ink leakage and other accidents, timely treatment.
Recommended for the same type of products
1.High Gloss Offset Ink
2.Medium Quick-Drying Offset Ink
3.Ordinary Economical Offset Ink
4.Offest UV Ink