Stimulus-Responsive Dispersing Agent for Industrial Deinking

The patent applies parameter changes by modifying the hydrophilicity parameter of the pigment particles through the use of dispersing agents with adjustable hydrophilic-lipophilic balance (HLB). By selecting dispersing agents with appropriate HLB values and molecular structures, the pigment particles can be made sufficiently hydrophilic for good dispersability during printing, yet retain enough hydrophobic character to allow flotation separation during deinking. This dynamic parameter adjustment resolves the contradiction between dispersability and deinking efficiency.

The patent employs composite materials by creating hybrid dispersing agent systems that combine both hydrophilic and hydrophobic components. These composite dispersing agents contain polar groups (such as carboxylic acid groups) for hydrophilic interaction with water and protic polar solvents, alongside non-polar hydrocarbon chains for hydrophobic interaction with air bubbles during flotation. This composite structure enables the pigment particles to exhibit dual characteristics: good dispersability in the printing phase and floatability in the deinking phase.

The patent extracts the harmful calcium carbonate precipitation step from the deinking process by replacing calcium salt jetting with alternative approaches. Instead of using calcium salts that react with carbon dioxide to form clogging precipitates, the patent employs organic dispersing agents that can be removed or transformed without generating harmful byproducts. This extraction of the problematic chemical reaction eliminates nozzle clogging while maintaining deinking effectiveness.

The patent introduces intermediary substances - specifically organic dispersing agents with carboxylic acid groups - that mediate between the pigment particles and the deinking process. These intermediaries provide the necessary hydrophobic character for flotation without requiring calcium salt addition. The dispersing agents act as intermediaries that enable deinking through their molecular structure rather than through calcium carbonate precipitation, thereby avoiding nozzle clogging.

The patent applies dynamics by using dispersing agents whose hydrophilic-lipophilic balance changes dynamically in response to pH conditions. The dispersing agents are designed with molecular structures that provide hydrophobic character at printing pH (maintaining color strength and adhesion) but can be transformed or removed under alkaline deinking conditions. This dynamic behavior allows the system to adapt its properties according to the operational phase, resolving the contradiction between color strength and deinking efficiency.

The patent applies preliminary action by pre-equipping the pigment particles with dispersing agents that are specifically designed to facilitate both printing and deinking. Rather than relying on post-printing chemical treatments that may compromise color strength, the dispersing agents are incorporated into the ink composition beforehand, providing built-in deinking functionality. This preliminary preparation ensures that deinking can proceed effectively without sacrificing the adhesion and color strength achieved during printing.