A breakthrough: the terminator of the "emulsification shackles" of traditional offset printing and UV ink
Publish Time: 2025-07-28
In the offset printing process, ink emulsification is a "chronic disease" that has long plagued the industry - traditional offset printing causes excessive ink emulsification due to uncontrolled water-ink balance, and UV offset printing causes emulsification adhesion due to leveling problems before UV curing, which can cause the gloss of printed products to decrease and dots to blur, and even cause production accidents such as plate blocking and dry plate. A large packaging and printing company once scrapped batch orders due to UV ink emulsification, with direct losses exceeding one million yuan. Today, a demulsifier designed specifically for offset inks is breaking this dilemma with "molecular disassembly" technology, becoming a "secret weapon" for printing workshops to improve efficiency and quality.1. Technical core: from "physical peeling" to "molecular disassembly"Traditional demulsifiers mostly reduce oil-water interfacial tension through surfactants, but there are two major defects:Poor selectivity: low compatibility with components such as photoinitiators and active diluents in UV inks, easy to destroy the curing system;Short-term effect: only temporary separation of oil and water can be achieved, and emulsification is easy to repeat during printing.The new generation of demulsifiers adopts the structure of "amphiphilic block copolymers". One end of the molecular chain is a strong polar group (such as carboxyl, sulfonic acid group), which can accurately anchor the hydration layer on the surface of the emulsified oil droplets; the other end is a long-chain alkyl or polyether chain, which prevents the oil droplets from re-aggregating through the steric hindrance effect. Taking DISUPER S19 as an example, its molecular weight distribution is narrow (PDI <1.2), and it can form a dynamic protective film in UV ink, which can maintain the leveling of ink even after multi-color overprinting. Experimental data show that UV ink with 2% DISUPER S19 can achieve oil-water separation within 30 seconds, and the adhesion of the ink layer is increased by 15% after curing.2. Demulsifier "goes out" to printing scene: application results are fully displayedScenario 1: Traditional offset printing - "ink savior" in high humidity environmentA medicine box printing company is located in a humid area in southern China. The humidity in the workshop in summer often reaches more than 80%. Traditional offset printing inks are prone to excessive emulsification due to water absorption, resulting in "white spots" on the surface of printed products. After the demulsifier was introduced, by adding 0.5% of the demulsifier component to the fountain solution, the interfacial tension between the ink and water was reduced from 32mN/m to 18mN/m, and the diameter of the emulsified oil droplets was reduced by 60%. Actual effect: After printing 20,000 sheets continuously, the number of plate blockages was reduced from 5 times a day to 0 times, the glossiness of the printed products was increased from 65° to 82°, and the customer return rate was reduced by 90%.Scenario 2: UV offset printing - the "leveling guardian" of high-speed printingA cosmetic packaging printing factory uses UV offset printing to produce high-end gift boxes. Due to the pursuit of high-speed production (12,000 sheets per hour), the ink is cured by ultraviolet light before it is completely leveled, resulting in "orange peel" on the surface of the ink layer. The demulsifier adjusts the ink viscosity curve to allow the ink to spread quickly under printing pressure, while suppressing the rebound of the emulsified oil droplets. Actual effect: The printing speed is increased to 15,000 sheets/hour, the ink layer smoothness (Ra value) is reduced from 1.2μm to 0.3μm, and the hardness of the ink layer after curing reaches 3H, which meets the friction resistance requirements of cosmetic packaging.Scenario 3: Mixed printing - the "compatibility master" of traditional and UVA publication printing company undertakes orders for textbooks (traditional offset printing) and picture albums (UV offset printing) at the same time, and needs to frequently switch ink systems. Residual ink is prone to cross contamination. Demulsifiers destroy the emulsified structure of residual ink, allowing it to quickly detach from the printing plate during the cleaning process. Actual effect: The plate change time is shortened from 45 minutes to 15 minutes, the water consumption for plate cleaning is reduced by 70%, and the plate's printing durability is doubled (from 200,000 prints to 400,000 prints).3. Technology extension: from "demulsification" to "full process optimization"The new generation of demulsifiers has broken through the single function and evolved into "printing process optimizer":Synergy with superdispersants: Adding demulsifier precursors in the pigment dispersion stage can prevent emulsification caused by pigment aggregation during the printing process (such as the compound system of Anjikang 6040 and demulsifier, which increases the dispersion stability of carbon black by 3 times);Intelligent responsive design: A laboratory is developing a pH/temperature dual-sensitive demulsifier that can automatically adjust the intensity of action according to the printing environment to solve the "one-size-fits-all" dosage problem of traditional demulsifiers;Biological-based substitution: Demulsifiers based on plant oils and fats have entered the pilot stage, and their degradation products can be completely decomposed by microorganisms, meeting the environmental protection requirements of food packaging printing.4. Industry impact: from "cost center" to "value creator"The application of demulsifiers is reshaping the cost structure of printing companies:Direct cost: Statistics from a certain company show that demulsifier investment accounts for 3% of ink costs, but the comprehensive benefits brought by reducing waste, speeding up, and reducing consumption are as high as 18%;Hidden value: By stabilizing printing quality, the company successfully entered the high-end pharmaceutical packaging market, and the unit price of orders increased by 40%;Social benefits: Reducing the discharge of cleaning waste liquid, a medium-sized printing plant reduced COD (chemical oxygen demand) by more than 10 tons per year, which is in line with the ESG (environment, society and corporate governance) investment trend."Industrial aesthetics" of demulsifiersFrom "passive firefighting" to "active prevention", the technological evolution of demulsifiers reflects the transformation of the printing industry from "extensive production" to "lean manufacturing". When a demulsifier can solve the emulsification problems of traditional and UV offset printing at the same time, and even be compatible with different printing scenarios through molecular design, it has surpassed the scope of "auxiliary agents" and become an "intelligent regulator" in the printing process chain. In the future, with the integration of nanomaterials and AI technology, demulsifiers may realize "holographic monitoring of the printing process", bringing more profound changes to the industry.
