Printability and application of the hottest ink cl

Printability and application of ink cleaner (Part 2)

technical indicators of ink cleaner

generally speaking, the technical indicators to measure high-quality ink cleaner mainly include:

1 Aromatics free

aromatic compounds have strong cleaning ability for inks, but the current foam granulator industry should pay attention to environmental protection. Aromatic compounds have many adverse effects on printing, so new ink cleaners should not contain aromatic compounds

the adverse effects of aromatic compounds on printing mainly include:

(1) aromatic agents will cause the expansion of rubber, affect the printing pressure, and easily cause printing quality problems

(2) it does not conform to environmental standards and human health standards

2. Based on vegetable oil

ink cleaners should be based on vegetable oil, not mineral oil

3. It has the characteristics of high flash point

at present, the flash point of international high-quality ink cleaners is above 55 ℃, and the flash point of thermosetting ink cleaners is above 100 ℃ during the cleaning process. The flash point of detergent must be higher than the minimum temperature in the printing channel in order to meet the safety standards of the workshop. The flash point of detergent in ordinary printing should be above 55 ℃, while in ultraviolet ink printing, the flash point of detergent should be higher than 70 ℃

international standard for ink cleaners international standard for ink cleaners

the standard for ink cleaners was internationally stipulated in 1995, as follows:

(1) all new machines (produced after the Convention) should be suitable for normal work production. When using cleaners with a flash point of 55 ℃ or higher, the production capacity of the machines is still within the normal range

(2) detergent with flash point lower than 21 ℃ cannot be supplied or used for cleaning printing rollers and blanket

(3) detergents with a flash point between 21 and 55 ℃ may be used before the date of this Convention when there is no other choice for technical reasons, but they are not allowed to be used on new machines

(4) manufacturers, suppliers, printers, employees and authorities will negotiate and propose substitutes for solvents, including the use of high flash point solvents (flash point of 100 ℃) and vegetable oil based cleaners to replace early solvents

(5) do not supply and use solvents containing halogenated alkane terpenes (turpentine), n-hexane, imine or amide

(6) the content of aromatic compound products in the solvent supplied or used shall be less than 0.1%

(7) the content of toluene and xylene in the solvent supplied or used shall be less than 10%

(8) the content of hydrocarbon in the solvent supplied or used shall be less than 10%

(9) infrequently used low flash point materials, such as blanket restorer or peeling ink remover, can continue to be used in small amounts if they contain methyl ethyl ketone, but they must be warned and trained in advance

(10) the suppliers and users of printing machines, materials and consumables work together to provide technical support and training with the help of relevant associations, so that users can adapt to new cleaning methods when using high flash point solvents. If necessary, they may also need to replace rubber blanket and rubber roller

characteristics of high-quality ink cleaner characteristics of high-quality ink cleaner

in terms of printability, high-quality ink cleaner has the following performance:

(1) it meets the requirements of environmental protection and health, does not contain aromatic compounds, and its flash point is higher than 55 ℃

(2) it has good cleaning ability for ink, and the cleaning degree of organic and inorganic compounds reaches more than 95%

(3) it has good adaptability to cots and blanket, and the expansion rate is not higher than 2%

(4) it has no corrosive effect on the printing plate and printing machine

(5) the main component of auxiliary detergent should be vegetable oil

auxiliary cleaning of ink roller

in the printing process, due to the influence of external conditions such as paper, ink and water quality, the influence on the cleaning effect of ink and the chemical suitability of printing cots, as well as the deformation caused by chemical factors, is becoming greater and greater. In modern printing, while using ink cleaner, we also use some chemical maintenance products for auxiliary cleaning, so as to ensure the complete removal of impurities remaining on the cot, and finally achieve the purpose of smooth printing. These auxiliary cleaning mainly include deep cleaning, enamel removal, rubber reduction, idling protection, dead ink softening, etc

1. Deep cleaning

is mainly carried out when the printing unit changes color, so it can also be used in the engine room to clean and maintain the ink roller and print spot color ink, which can significantly shorten the downtime and reduce the number of papers

2. Calcium removal

the water quality provided to the fountain system of lithographic press in different regions is different, and the calcium carbonate and other minerals contained in it are also different. At the same time, the hardness of water is also different. Under normal circumstances, the cot will absorb calcium carbonate and other minerals, which will reduce the ability of the cot surface to transmit water and ink, so it is very necessary to remove calcium

3. Idling protection

when the contact surface of the ink roller rotates without ink lubrication, it will cause permanent damage to the surface of the ink roller in a very short time. Therefore, special chemical maintenance products need to be used during the idling of the ink roller to prevent the idling of the ink roller from causing damage to the strategic surface of Nanjing's active docking with the country's "made in China 2025" or excessive high temperature

4. Regular cleaning and reduction

long time printing will cause stubborn hard ink and other impurities in the rubber, which will lead to the glaze of the rubber roll surface and the increase of hardness. Therefore, it is necessary to thoroughly clean the rubber and restore its elasticity regularly

5. Enamel removal

due to the accumulation of time, the residual substances formed on the rubber surface must be cleaned

(2) determination of yield limit of low carbon steel σ S and strength limit of cast iron σ B source: