The reason for choosing a good ink cleaner

As we all know, the main body of the world printing industry is offset printing. Offset printing ink is transferred to the substrate through ink rollers, blankets, etc. The ink roller and blanket are durable goods. To ensure its normal operation, regular cleaning and maintenance are very important. This includes 3 kinds of cleaning: routine cleaning after printing every day; changing color before cleaning ink; regular thorough maintenance cleaning.

In this sense, ink cleaning is a very important task for printing companies. In addition, ink cleaning agents are very large quantities of printing consumables. According to management, printing companies should attach great importance to the procurement and selection of ink cleaning agents, but the current situation Yes, a large number of printing companies partially or completely use gasoline and kerosene as ink cleaning agents. A survey shows that even in Beijing where the printing industry is relatively developed, almost none of the printing companies totally abolishes the use of gasoline and kerosene to clean printing presses. In fact, printing companies are very clear about the possible adverse effects of using gasoline and kerosene, but due to factors such as the wide range of sources of gasoline, kerosene, fast drying speed, and relatively low prices, printing companies cannot refuse. These advantages stand out in comparison with ink cleaners available on the market: Ink cleaners have specific conditions for specific printers, blankets, rubber rollers, etc.; special ink cleaners are expensive; supplies are also available Cannot guarantee full timeliness and so on.

Let gasoline, kerosene class

(1) Poor results The use of gasoline and kerosene for cleaning ink has the following drawbacks.

(2) Although the use of gasoline and kerosene for the conventional cleaning of rubber rollers and blankets is very convenient and the effect is satisfactory, the water-soluble components such as paper wool, paper powder, and gum arabic attached to the rubber roller are used for gasoline and kerosene. But nothing can do it. A variety of impurities layered on the surface of the roller, it will close the original capillary pores on the surface to form a smooth crystalline layer, so that the roller size changes, severely affect the printing pressure, ink roller transfer performance decline , resulting in printing "meat bar", "flat net hair" and other printing failures. At the same time, a large amount of aromatic compounds contained in gasoline and kerosene can also cause the rubber to swell, affecting printing pressure and printing quality.

(3) Safety hazards Gasoline and kerosene are highly flammable liquids. The flash point (that is, the temperature at which steam encounters an open flame) is only twenty degrees. If the ventilation facilities in the printing plant are not good, it is prone to fire and other hazards. Happening. This proved to be the case. Many printing companies exploded when workers used gasoline cleaning presses.

(4) Unfavorable environmental protection Gasoline and kerosene contain a large amount of VOCs, causing serious environmental pollution and failing to meet environmental safety standards, and causing greater harm to employees' health. At the same time, most printing companies dumped the method of directly discharging gasoline and kerosene that had been washed with ink into the sewers. Needless to say, the pollution to the soil and water quality was at the same time. At the same time, the gasoline and kerosene that floated on the surface of the water were relatively high at outdoor temperatures. In the season, there is also the danger of explosion.

(5) Facing elimination In order to better promote the development of the printing industry, various countries in the world have started to formulate regulations and standards for ink cleaning agents (car wash water) in 1995. These mainly include: The flash point is lower than 21°C. Ink cleaning agents cannot be used for the cleaning of printing blankets and blankets (such as gasoline); solvents containing halogenated alkane terpenes (turpentine), n-hexane, imines, or acid amines must not be supplied and used; aromatics in solvents The content of the compound should be less than 0.1%; the content of toluene and xylene in the solvent should be less than 10%. At the same time, many printer manufacturers, especially high-end printing equipment manufacturers, will rigorously test and regulate the use of chemicals on their printing equipment. Such as Heidelberg company has been rigorously tested, there are three types of car wash water that can be used on Heidelberg presses: 60, Superdot and Varn. In order to undertake international business, some printing companies must pass the ISO9001 quality management system certification and ISO14001 environmental management system certification in accordance with the requirements, and naturally prohibit the use of gasoline and kerosene as ink cleaning agents.

If it is said that printing companies used gasoline and kerosene in the past as a common choice to expand profits, then in today's increasingly fierce competition in the printing industry, using only petrol and kerosene to clean the ink in consideration of the material cost at the moment is a stare This is because it has significantly affected the social benefits and overall economic benefits of the printing industry. With the large number of imported high-end printing equipments being put into use, as well as the security and environmental protection awareness of the printing company operators, environmental-friendly ink cleaners (car wash water) will become the main cleaning solvent for the rubber rollers in the future. Understanding Ink Cleaning Agents In fact, the ultimate goal of various ink cleaning agents on the market today is to wash off impurities such as ink. In the printing process, many impurities generated by ink, water, and substrates can be roughly divided into two categories: One is a solvent type, that is, soluble in organic solvents such as ink oils, resins, gum oils, waxes, binders, and acid and alkaline substances in inks and additives; the other is water-soluble, That is soluble in water or affinity to water, such as gum arabic, casein, paper hair, paper powder, fillers and other inorganic compounds and hydrophilic pigments.

In this way, in order to achieve the purpose of cleaning, the cleaning principle is roughly the same, and the composition also includes the following types.

(1) When the content of hydrocarbon cleaner is more than 50%, hydrocarbons can be divided into aliphatic hydrocarbons and aromatic hydrocarbons according to their molecular structures, all of which have a good dissolving effect on the ink. Among them, aliphatic hydrocarbon molecules contain a chain structure of carbon molecules, can not be dissolved in water, no harm to the human body, rubber rollers and the environment; while the aromatic hydrocarbon molecules contain carbon molecules in the ring chain structure, The human nervous system has adverse effects, and long-term use may lead to cancerous lesions, which can expand the rubber polymer and have a certain influence on the rubber roller. Therefore, the content of the international ink cleaning agent stipulated in the quality standard should be less than 0.1%.

(2) Emulsifiers can promote the mixing of oil and water, resulting in emulsification; general flash point cleaners contain emulsifiers and do not cause residual chemicals on the rollers and blankets.

(3) Anti-corrosion agent Since the cleaning agent needs to be provided with water for cleaning, the anti-corrosion agent has the effect of preventing water corrosion. Currently, the ink cleaning agents on the market are mainly divided into two parts according to their sources: First, they are imported, their products basically comply with the relevant international quality standards, but they are expensive; second, they are made domestically, their prices are moderate, but the quality is uneven, and some products have flash points. If it is too low, it can easily cause fires. Some products have high levels of aromatic compounds and poor environmental protection. According to the type of technology, the ink cleaning agent can also be divided into two types: one is a pure solvent type, and it needs to be mixed with fresh water when used, but the ratio has an optimal value, and the best can only be achieved when this ratio is reached. The cleaning effect. In actual production, machine operators often cannot control the ratio of solvent and water very well, which not only results in a lot of waste, prolongs the cleaning time, but also affects the cleaning effect; the other is that the solvent has been used before production. Mixing with water in the best ratio, and adding the emulsion type ink cleaning agent made of emulsifier, its droplet size is very small, it is easy to penetrate the ink layer on the surface of the rubber roller, the cleaning effect is excellent, and the amount is only equivalent to gasoline 1/4 to 1/5. This type of car wash water is the development direction of car wash water products in the future. Generally speaking, the high-quality ink cleaning agent we are referring to is mainly an emulsion ink cleaning agent composed of two organic solvents with different flash points, rubber antioxidants, and surfactants capable of forming stable water-in-oil emulsions. By emulsifying the solvent with water to emulsify the solvent into a W/O type emulsion system, gasoline can be directly substituted for ink cleaning. The emulsion type car wash water is not flammable, and the storage safety is good, but the transportation volume is large and the use cost is increased. The cleaning performance of the emulsion car was related to the composition of the formula, especially the choice of solvent and active agent. At the same time, because the emulsion car wash water is a thermodynamically unstable system, it has poor stability and is easy to be stratified. Once it is stratified, it is difficult to deink, which affects the use, so its storage period is not too long. At present, some manufacturers have also introduced new types of ink cleaning agents, such as micro-emulsion car wash water, which do not require configuration and the thermodynamic system is stable, which makes up for the shortcomings of traditional ink cleaning agents.

However, in general, ink cleaners are superior to gasoline and kerosene in that they are highly efficient, energy-saving, environmentally friendly, and safe. They also have the effect of solvents and water. They not only remove ink, but also remove some water-soluble properties such as paper. The amount of dirt is small compared to gasoline (the same ink roller is used, and the amount of ink cleaning agent used is only 50% or less of gasoline). The ink cleaning agent has a slow volatilization rate, can fully exert its effect, and can greatly save the amount, but relative to gasoline. In terms of drying speed, it is slower. Not only use, we advocate the use of ink cleaning agent, on the one hand because the ink cleaning agent can save the printing company's overall cost; the other is mainly to hope that as a corporate social responsibility, must be based on their actual situation The environment and human health assume their own social responsibilities. Therefore, even if you disregard gasoline and kerosene and use an ink cleaning agent, it does not mean that everything is available, and the ink cleaning agent is not perfect. Although the ink cleaning agent has its own impact on the human body and the surrounding environment compared to gasoline and kerosene. To be small, but does not mean that there is no pollution; at the same time, like gasoline and kerosene, ink and other substances dissolved in the ink cleaning agent are harmful to the human body and the surrounding environment can not be ignored.

Therefore, when we choose the ink cleaning agent (including ordinary and UV) do not map cheap, be sure to choose a good, environmentally friendly product! In order to truly achieve the above effect!