From suspension toward emulsion and mini-emulsion polymerisation to control particle size, particle size distribution, and sphereness of printing toner

Abstract

Purpose Printing toners are polymer composites accountable for transmission of digital images onto target substrates. Bearing in mind the ever increasing demand for high quality digital printing, modification and/or integration of existing techniques for manufacturing toners with favourable morphological and colour characteristics appears of vital importance. The present study aims to uncover the significance of in-situ polymerisation method, i.e. suspension, emulsion and mini-emulsion to control the microstructure of toner particles (particle size, particle size distribution and sphereness) while keeping the energy required for polymerisation along with reaction conversion at a reasonable level. Design/methodology/approach Assessment of particle size, particle size distribution and reaction conversion visualised the potential of suspension, emulsion and mini-emulsion polymerisation techniques to control microstructure, and colour characteristics of synthesized toners as well. Findings The results provided support for the fact that either the emulsion or mini-emulsion polymerisation routes will result in toners having an acceptable particle size and particle size distribution in the presence of a redox precursor. The higher monomer conversion at low temperature, as compared to the suspension polymerisation, was noticeable. Practical implications Analysing the glass transition temperature and colour characteristics of the resulting toners elucidated the superiority of mini-emulsion with respect to the other two cases which ranks this method on account of application. Originality/value For the first time, mini-emulsion route was put into practice and toners with acceptable colour and microstructure features were synthesised. In spite of lower polymerisation temperature and higher conversion of mini-emulsion compared to suspension and emulsion polymerisation techniques, further investigations are required to fine-tuning the properties of toners produced through this method.

Intelligent modeling and optimization of emulsion aggregation method for producing green printing ink

“…An approximately similar tendency was saw in L*(lightness), which can be ascribed to the reality that this color specification correlates fairly good with the PS. More evidence comes from the reality that the volume of carbon black has hardly been reformed by the researchers, therefore, the L* of toner should be monotonically governed by the size of toner particles [3,8]. In this point of view, the incompetence of the utilized model to account for a* and b* can be rationalized.…”

“…This parameter can change the digital printing characteristics of laser printers and photocopiers. It is worth denoting that, majority of toners physical properties are dependent on synthesis method and well-established methods can lead to favored homogeneity, particle size (PS), particle size distribution (PSD) and shape of toner particles in final product [8]. However, ordinary approaches normally based on grinding were founded to be unsuitable to produce small particles with narrow size distribution and spherical shape [9].…”

“…Based on a series of prior publications, Diverse black printing toners have already been manufactured via suspension [8], emulsion aggregation [9], emulsion, and mini-emulsion [10] procedures with an entirely a large variation of physical and color qualities. Toners with different nature were also prepared by changing the kind and amount of coloring agent [11,12,16].…”

Influence of redox initiator component ratios on the emulsion copolymerisation of vinyl acetate and neodecanoic acid vinyl ester

“…Slowing down the conversion rate through process optimisation also reduces the risk of leakage when approaching the boiling point of the chemicals used, therefore increasing the safety of employees or workforce. 30 Yet, until now, very few emulsion polymerisations have been successfully performed at lower temperatures while achieving high overall conversions. For instance, although the reaction temperature for poly vinyl acetate was reduced to the range of 8–22 °C by using a redox system composed of potassium persulfate and dimethylethanolamine, the overall conversion was limited to 48–88% after 4 h of reaction, therefore resulting in a comparatively low space-time-yield.…”

Micro powder poly lactic acid/carbon black composite as a bio printing ink

“…It should be noted that just using a suitable polymer binder is not adequate and the production method should be justified. Consequently, the author has applied the suspension, 15 emulsion and mini-emulsion 16 polymerization techniques to produce toners with a rather wide variety of physical and color attributes. Besides, the author has fabricated toners with different characteristics by changing the kind and quantity of the coloring agent.…”