Environment and safety in the hottest flexographic

Environment and safety in flexographic printing

today, China paper takes you to understand the environment and safety problems in the process of flexographic printing. This paper makes a detailed analysis of the main processes and material applications in flexographic printing in terms of printing environment and safety, and puts forward specific methods for the control of environmental pollution factors and the improvement of printing plant environment

green environmental protection has become the development theme of the new century. The greening problem in modern printing has become a major problem that hinders the sustainable development of the printing industry. It is urgent to start green projects, develop green products and meet the requirements of environmental protection. With the emergence of various green products, better green packaging, more practical green printing materials and corresponding printing methods are inevitably required. Flexographic printing is complying with the needs of the times, and has increasingly become the preferred green printing process at home and abroad

flexographic printing was originally called "aniline printing", which was named after the volatile ink printing made of aniline dye. Because aniline is toxic, its printing range is greatly limited. With the continuous development of powder flexographic printing technology and the increasingly wide range of applications, as well as the promotion of non-toxic, non residual latent agent, non environmental pollution water-based ink, UV oil and drunk soluble oil, it meets the requirements of environmental protection and green packaging, so it can develop rapidly. Although flexographic printing has greatly reduced the pollution to the environment compared with other printing methods, it is only relative. In the flexographic printing process, no matter how advanced technology, process and materials are used, it can not be completely and pollution-free to the environment. Therefore, to realize the further greening of flexographic printing, in addition to pursuing perfection in materials and processes, flexographic printing operators and managers need to make greater efforts in practice to reduce environmental pollution. The following will discuss several important factors that affect the environment in flexographic printing

environmental factors in the process of plate making

1 An important aspect that affects the environment in the process of plate making is the application of developer. Flexible plate has experienced the development process from rubber plate to photosensitive resin plate. Because of the excellent characteristics of photosensitive resin plate, it has been widely used. Flexographic plate washing is completed in a special plate washing machine. The developing solution mostly takes the grasping hydrocarbon solvent (triazine ethylene) as the main solvent, but triazine ethylene is toxic and its volatility is very strong. When using, it should be noted that the tertiary ethylene vapor in the air cannot exceed the poisoning limit. In addition, when light, air and water coexist, ethylene in three atmospheres will decompose and produce harmful hydrogen atmosphere acid gas, causing metal corrosion. Therefore, there must be special cleaning equipment in the short cut glass fiber process produced by Guo Langsheng, which also produces fine glass melt. The equipment itself can recycle the developer for recycling, and it is best to be in a closed form. Another better way is to develop solvents with less side effects to replace tertiary ethylene

2. Debonding process

debonding is to use light or chemical methods to drill the layout. The purpose is to remove the drillability of the plate surface and enhance the power in the powder

① chemical method

the method is to immerse the dry printing plate into the prepared drilling solution for treatment. There are two kinds of chemical drilling graded treatment (bleach aqueous solution) and Australian chemical treatment (hydrochloric acid and Australian Chemical aqueous solution). Obviously, these two solutions are extremely compatible with the environment, so this method has gradually become unavailable in the process of drilling

② illumination method

this is a commonly used method, which is completed by irradiating the Australian solution coffin with ultraviolet C (UV-C light source). Compared with the first method, the environmental pollution caused by the light method is much lighter, but it should be noted that the solution after short wave radiation in the light method is also harmful to the environment, and the waste liquid should be properly treated

at labeexpo in Chicago in September 2000, DuPont launched the Saili express system This is a completely digital drying and plate making system. In essence, it is a hot working version, and the whole processing process is completely dry

because it does not need to use solvents, it completely avoids the environmental pollution caused by solvents. In addition, it also greatly reduces the plate making time, and the processing process is faster without drying

environmental factors in ink application

at present, oil is the largest pollution source in the printing industry. The annual output of oil in the world has reached 3million tons. Every year, the global VOC (organic volatile matter) pollution emissions caused by ink have reached hundreds of thousands of tons. These organic volatiles can form a more serious greenhouse effect than CO2, and will form oxides and photochemical smog under the irradiation of sunlight, which will seriously pollute the atmospheric environment, which has attracted extensive attention from all aspects. Among various printing methods, only flexographic printing has widely used environmental friendly green printing materials - water-based ink, UV ink and drunk ink. Here we mainly introduce the first two

1. Water based ink

the biggest feature of water-based ink is that it significantly reduces the emission of VOC (organic volatile matter), f thus preventing air pollution, improving the printing environment, and is conducive to the health of workers. It can completely eliminate the harm of some toxic and harmful substances in solvent based ink to human body and the pollution of packaging products, and improve the overall environmental quality. F is especially suitable for packaging and printing products with strict sanitary conditions, such as food, beverages, drugs, etc. In addition, it can not only reduce the fire hazard and hidden information caused by static electricity and flammable solvents, but also reduce the residual solvent odor on the surface of printed matter

as people adopt low-noise linear conjugate internal gear pump, the voice of environmental protection is getting higher and higher, and the position of water-based ink will become more and more important, and its use will be more widely. Therefore, we must more strictly control the characteristics of water-based inks to minimize environmental pollution. Although water-based inks significantly reduce the emission of VOC, we hope to control this emission f to a lower level. In the air cleaning program implemented by California a few years ago, the content of organic volatiles in water-based inks is required to be no more than 3%. In addition Many users and manufacturers also have restrictions and requirements on the heavy metal content of F in water-based inks, which means that pigments with high content of heavy metal ions should be correctly selected in the formulation of water-based inks

ink

UV radiation curing products (including UV ink and UV varnish) are known as "new green industrial technology for the 21st century" for their high efficiency, energy saving, solvent-free emission, environmental pollution-free and excellent product performance, and their safety has been recognized by the U.S. Environmental Protection Agency. In the past 10 years, the application of UV varnish and UV varnish has become increasingly popular. According to statistics, the use of UV ink for flexographic printing in the United States in 2001 has reached 3500 tons

in terms of environmental protection, UV ink is indeed a very ideal ink. It should be noted that most UV products can be regarded as skin irritants before drying. However, due to the low volatility of these products, if the habit of wearing skin care gloves and eye masks can be maintained during operation, such problems will be reduced. In addition, it is necessary to provide the subsequent treatment of the exhaust system, because the old UV ink will emit oxygen

environmental impact in roller cleaning

in flexographic printing, the roller is a very important single in the process of ink transfer. Its surface is covered with particularly small holes. Through these holes, ink transmission is realized, and ink blocking holes are a headache in flexographic printing. Usually, the hole blockage is caused by the hole of the corrugated roller being blocked by the dry oil button during the working process. Therefore, in the process of printing, it is necessary to clean the wrinkle roller in time

generally, there are the following cleaning methods:

1 Strong corrosion chemical cleaning method

apply corrosive cleaning agent (generally alkali solution) evenly on the surface of the roller. If necessary, wrap a layer of plastic products on the surface of the roller to prevent the volatilization of the chemical solution. When the roller is ablated for hours, wait until the cured ink is fully softened, and then clean the roller with water or alcohol (acid solution such as acetic acid is not available) combined with manual cleaning method. This kind of cleaning method has good cleaning effect, but it has a certain corrosive effect on the corrugated roller and will cause environmental pollution

2. Spray cleaning method

spray baking soda softening cleaning medium onto the surface of the roller to break the solidified ink to achieve the purpose of cleaning. Baking soda is soluble and non-toxic. Its crystal is easy to break when it collides with other substances, and will not damage the surface of the roller and the ink hole wall. Therefore, this cleaning method has good cleaning effect and has promotion and use price

3. Ultrasonic ripple washing method

immerse the part roll in an ultrasonic cleaning tank filled with chemical cleaning solution. During cleaning, the corrugated roll rotates slowly The frequency conversion device that can send high-frequency sound waves in the pool starts to work, causing the solution to vibrate and produce bubbles, causing inward explosion. The continuous inward explosive force drives the ink out of the hole and flows away with the cleaning solution. This method is also very conducive to environmental protection

from the above three methods, it can be seen that the latter two methods have low impact on the environment, while the third cleaning method has high investment cost and complex process. Therefore, each printing factory should choose the appropriate way to clean the corrugated roller according to the actual situation of the factory

recycling system

the recycling of storage containers and cleaning cloth is jc890 ⑵ 001 masonry mortar and plastering mortar for autoclaved aerated concrete (for recycling and reuse "has been widely established in many countries.

the meaning of recycling is: the reuse and treatment of a part of a product in a recycling system or its trial produced specific products. The recycling system produces secondary raw materials, and in this way saves resources and reduces waste, thereby reducing the degree of pollution to the environment.

through the above analysis, we can have several impacts on flexographic printing The main factors of environment and safety shall be effectively controlled. Of course, these control methods are not uniform. In the actual production process, each printing factory should choose the appropriate environment and safety improvement methods according to the actual situation of its own factory

statement: This article is reprinted. The purpose of publishing this article is to transmit market information more widely. The content of this article is for reference only. The copyright of this website article belongs to the original author and the original source. The content is the author's personal views, which does not mean that this website agrees with his views and is responsible for its authenticity. This website only provides reference and does not constitute any investment and application suggestions. Some articles on this website are reprinted and are not used for any commercial purposes. We have notified the author and source as much as possible. If there is any missing or inappropriate information, please contact us in time, and we will correct or delete the relevant content immediately according to the requirements of the copyright owner. This website has the final right to interpret this statement