The effect of ultraviolet‐curable water‐borne polyurethane acrylate binder concentration on the printing performance of synthetic leather

Abstract

In this paper, synthetic leather samples were screen printed with pigmented pastes including two types of photoinitiators and three different concentrations of ultraviolet (UV)‐curable water‐borne polyurethane acrylate binder. The curing process was conducted under different combinations of lamps (gallium, mercury, gallium/mercury and gallium/gallium/mercury) at three power levels. Abrasion resistance, crock fastness, hardness and colour strength were investigated. Chemical changes in the clear and pigmented film structures because of UV curing were analysed by Fourier Transform‐infrared spectroscopy measurements. In hardness measurements, the highest hardness values were obtained with clear and pigmented formulations which have the highest solid content (57%). In colour measurements, higher K/S values were obtained in samples printed with the formulation having a binder concentration of 46%. Wet crock fastness values improved as the energy level increased during curing, and the highest values were obtained with a formulation which had a binder concentration of 57%. Greater amounts of binder in the formulations and increased amounts of energy applied to the surface during curing increased the hardness value of the prints, thus better abrasion resistance was obtained. Overall results suggested that the highest hardness, crock fastness and abrasion resistance values were obtained with the formulation with a binder concentration of 57%. However, for ease of application, printing efficiency and colour strength, the formulation with a binder concentration of 46% is recommended for printing, and curing under consecutive passes with gallium and mercury lamps at 120 W/cm is proposed in terms of energy efficiency and printing performance.

Synthesis of ultraviolet (UV)-curable water-borne polyurethane acrylate binders and comparison of their performance for pigment printing on synthetic leather

“…The printing performance results (Table 9) of PEG-C binder, synthesized with PEG 2000 polyol and low DMPA amount (4.89 wt. %), which provided the best abrasion resistance and crock fastness values, were compared with those of a commercial binder as reported in our previous studies (Baysal et al , 2018a, b). According to results, samples printed with synthesized binder showed lower crock fastness and abrasion resistance values than those of commercial binder.…”

“…UV-curable printing pastes (solid content: 46%), including commercial/synthesized WPUA binder, equal photoinitiator (Omnirad® 819 DW and Omnirad® 500) ratio (1:1), pigment concentration of 3% and other additives, e.g. wetting agent, defoamer, thickener and ammonia solution, were prepared as reported in our previous studies (Baysal et al , 2018a, b). The printing formulations were prepared as given in Table 4.…”

“…Different from the researches reported in the literature, in this study, WPUA binders were synthesized using two different types of polyols (poly (propylene glycol), PPG 1000 and PPG 2000 and poly (ethylene glycol), PEG 1000 and PEG 2000 ) at different molecular weights and DMPA (2,2-bis(hydroxymethyl) propionic acid) at different amounts and their performance for pigment printing on synthetic leather were compared. The synthesized binders were employed in the preparation of pigmented screen-printing formulations as reported in our previous studies (Baysal et al , 2018a, b). The effect of different type of polyols and DMPA amounts used in binder synthesis on the UV-curable pigment printing performance on synthetic leather was investigated and the results obtained were compared with those of a commercial WPUA binder.…”

Effect of pigment colour on the printing performance of synthetic leather using a ultraviolet‐curable water‐borne polyurethane acrylate binder

“…Previously, we reported on the effect of the water-borne polyurethane acrylate binder concentration and photoinitiator ratio on the UV printing performance of synthetic leather [20,21]. In the current study, we aimed to determine the effect of different colour pigments on the UV printing performance of synthetic leather samples.…”

Colour and gloss properties of pigment‐printed synthetic leather using an ultraviolet‐curable water‐borne polyurethane acrylate binder and two photoinitiators at different ratios

“…In a recent study, Baysal et al examined the effect of binder concentration on abrasion resistance, crock fastness and K/S of pigment-printed and UV-cured synthetic leather samples. The results showed that it was possible to obtain high quality and durable pigment prints on synthetic leather sample using a UV-curable formulation including an equal ratio of photoinitiators (Omnirad 819 DW and Omnirad 500) with a binder concentration of 46% [22].…”