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Toner is a crucial dry colorant composite used in printing based on the electrophotographic process. The quality of printed images is greatly influenced by the toner production method and material formulation. Chemically in situ polymerization methods are currently preferred. This paper aims to optimize the characteristics of a composite produced through emulsion polymerization using common raw materials for electrophotographic toner production.

Emulsion polymerization provides the possibility to optimize the physical and color properties of the final products. Response surface methodology (RSM) was used to optimize variables affecting particle size (PS), PS distribution (PSD), glass transition temperature (T_g°C), color properties (ΔE) and monomer conversion. Box–Behnken experimental design with three levels of styrene and butyl acrylate monomer ratios, carbon black pigment and sodium dodecyl sulfate surfactant was used for RSM optimization. Additionally, thermogravimetric analysis and surface morphology of composite particles were examined.

The results indicated that colorants with small PS, narrow PSDs, spherical shape morphology, acceptable thermal and color properties and a high percentage of conversion could be easily prepared by optimization of material parameters in this method. The anticipated outcome of the present inquiry holds promise as a guiding beacon toward the realization of electrographic toner of superior quality and exceptional efficacy, a vital factor for streamlined mass production.

To the best of the authors’ knowledge, for the first time, material parameters were evaluated to determine their impact on the characteristics of emulsion polymerized toner composites.

The purpose of this study was to investigate the association of individual and environmental indicators with body mass-index-for-age-z-score (BAZ) of female adolescents living in the North-West of Iran.

In this cross-sectional study, 380 female adolescents aged 16-18 years were selected from two major ethnic groups (Azeri and Kurd) in Urmia city selected by stratified cluster sampling method. In total, 13 high schools (9 public and 4 private) were selected across all municipality zones of Urmia city. BAZ was calculated by Anthro-Plus software. Demographic and socioeconomic information of samples were collected by a questionnaire through interviews. Home environment features (including physical activity facilities, television, computer games and social media use, food consumption habits and family rules) and school environment features (including socioeconomic status [SES], physical activity facilities, food consumption habits) were evaluated by two separate self-constructed questionnaires via an interview with adolescents and schools’ deans, respectively.

Azeri adolescents had parents with higher education and job level and higher SES compared to Kurds (p = 0.000). A higher percent of Azeri adolescents were obese than their Kurd counterparts (p = 0.006). No association was found between individual factors and BAZ in each ethnic group. Considering home environment characteristics, in Kurd adolescents, the maternal occupational level was positively associated with BAZ (p = 0.02). With regard to school environmental features, accessibility of physical activity facilities in school was inversely associated with BAZ only in Kurds (p = 0.005).

To the best of the authors’ knowledge, this is the first study to investigate various environmental factors in association with adolescent’s overweight/obesity prevalence in different ethnical groups in northwest Iran.