This study reports on the colour and gloss properties of pigment‐printed polyurethane‐based synthetic leather using an ultraviolet (UV)‐curable water‐borne polyurethane acrylate binder and two types of photoinitiators (Omnirad 819 DW and Omnirad 500) at different ratios. The UV curing of printed synthetic leather samples was conducted with gallium and mercury lamps, either singly or in combination, at three different power levels. Chemical changes in the cured films because of the polymerisation of the UV‐curing process were analysed by Fourier Transform‐infrared spectroscopy, which showed that the polymerisation reaction occurred after UV curing in both the clear and in the pigmented films. The Omnirad 500 photoinitiator is more effective in surface curing and the Omnirad 819 DW photoinitiator is more effective in deep curing. The Omnirad 500 photoinitiator caused the gloss values to drop significantly, especially in the formulation including both photoinitiators, Omnirad 819 DW and Omnirad 500, at a 1:2 ratio, respectively. In the formulation including a higher ratio of the Omnirad 819 DW photoinitiator, higher gloss values were obtained compared with the formulation including a higher ratio of the Omnirad 500 photoinitiator. Considering all the results, the highest gloss value of 20.96 was obtained with samples printed with the formulation of the two photoinitiators at an equal ratio (1:1) cured under a gallium/mercury lamp combination at a power level of 90 W/cm. Moreover, the highest K/S value of 10.86 was obtained with samples printed with the formulation of the two photoinitiators at an equal ratio cured under the gallium lamp at 90 W/cm.
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.
The effect of pigment colours, cyan (C), magenta (M) and yellow (Y), and a blend of these (CMY blend) on the printing performance of synthetic leather using a ultraviolet (UV)‐curable water‐borne polyurethane acrylate binder and two types of photoinitiators was investigated. The curing process was carried out at different radiation doses using gallium and mercury UV lamps in combination. The performance of the prints was evaluated with abrasion resistance, crock fastness, gloss and hardness values and K/S. Chemical changes in the cured film structures due to UV curing were analysed by Fourier Transform–infrared spectroscopy measurements. The highest hardness values for clear and pigmented cured films were obtained with a gallium and mercury lamp combination at the highest energy density (1529 mJ/cm2). The highest K/S was obtained for the sample printed with the formulation including the C pigment and cured under a gallium and mercury lamp combination at low energy density (398 mJ/cm2). The M‐pigmented film displayed the highest hardness and abrasion resistance, whereas lower values were obtained with films pigmented with Y and C, and CMY blend, successively. The highest dry and wet crock values were obtained with the formulation including the M pigment. CMY‐pigmented film showed the highest gloss values at all energy densities. The pigment colour affected the curing degree of printed films due to the different absorption/transmission intervals of each colour in the UV spectrum.
In the present study, the electrospinning method was used to develop β–cyclodextrin functionalized polyvinyl alcohol nanofiber webs. The electrospinning parameters were adjusted in order to obtain uniform nanofiber webs by incorporation of varying concentrations of polyvinyl alcohol and β–cyclodextrin in the solutions. Subsequently, β–cyclodextrin/Vitamin C inclusion complexes were added into the polyvinyl alcohol solution, and adjusted parameters were used in the electrospinning process of functionalized polyvinyl alcohol nanofiber webs containing β–cyclodextrin/Vitamin C inclusion complexes. The formation of nanofiber webs was demonstrated by using Scanning Electron Microscopy. The presence of the inclusion complex in the functionalized electrospun polyvinyl alcohol nanofiber webs was proven by using ultraviolet–visible spectroscopy and Fourier Transform-Infrared Spectroscopy. Consequently, it was achieved to functionalize polyvinyl alcohol electrospun nanofiber webs by incorporating β–cyclodextrin/Vitamin C inclusion complex, which might be considered to have useful applications in cosmetics, personal-care products, and topical drug delivery.
In this study, the flame retardancy of ultra violet (UV) curable polyurethane acrylate (PU) coated films were enhanced. For this aim, alumina trihydrate (ATH) filling material was mixed with the pastes including a photoinitiator and a UV curable PU. ATH filling ratio was preciously adjusted to obtain a uniform coating. The coated films were cured with a UV curing system equipped with gallium (Ga) and mercury (Hg) lamps. The chemical changes and the curing degree of the UV cured films were examined by a Fourier Transform Infrared Spectrum (FTIR) and a pendulum hardness tester. The thermal properties of the UV cured films were evaluated using a Differential Scanning Calorimeter (DSC). Moreover, vertical flammability and limiting oxygen index (LOI) measurements were conducted in order to determine the burning behavior of the UV cured films. The successful curing of the films was evidenced by means of FTIR results. The addition of ATH slightly increased the hardness values of the films. DSC results showed that ATH addition not only increased the enthalpy values but also enhanced the flame retardant property of the coated films and maximum LOI was achieved as 31.5%.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.