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UV curing processes of materials have to be specially designed accordingly in order to obtain the optimized property for different electronics applications. The purpose of this study is to characterize and study the curing and thermal behavior of a two‐component epoxy‐based UV curable coating in electronics assembly with various thermal analysis techniques. Curing behavioral change in terms of UV light, UV exposure time, wavelength, modulus, thermal stability, organic volatile outgassing and volume was discussed. Process optimization of coating materials that were UV cured at 30°, 100° and 150°C for 1 and 10 min was further investigated. Moreover, the relationship between photocuring conditions and the resultant surface hardness was studied and correlated from the results of dynamic microhardness measurements. Thermal and hardness properties of the above processed coating materials before and after isopropyl alcohol saturation were also investigated.

The purpose of this paper is to prepare ultra-violet (UV)-curable inkjet inks for textile printing application. The influence of both type and component ratio of monomer/oligomer on the quality of the desired viscosity range is studied. Moreover, the effect of pigment/resin ratio on the rheological behaviour of the ink has been studied.

Aqueous dispersions of nanoscale organic pigments were prepared through ball milling and ultrasonication. The dispersed pigments were encapsulated into UV-curable resin via miniemulsion technique, using different types and component ratios of monomers and oligomers.

It was found that the monomer/oligomer ratio of 2:3 and the pigment/resin ratio of 2:1 gave the most stable miniemulsion dispersions and provided the most suitable rheological range for inkjet printing inks.

As the rheology of the ink is optimised, most of the problems associated with the jetting process could be avoided.

This method of using UV-curable encapsulated inks eliminates the usage of binders, which are the principal factor for nozzle clogging of the print head. In addition, binders are responsible for the coarse handle of the printed textiles.

The UV-curable inks were viewed as a green technology by the US Environmental Protection Agency.

This method is simple and fast and requires low cost. In addition, it could find numerous applications in surface coating.

The purpose of this paper is to encapsulate aqueous dispersions of nano‐scale CI Pigment Red 122 prepared through ball milling into UV‐curable resins, 1,6 hexanediol diacrylate (HDDA, monomer), and polyester acrylate (oligomer) using the mini‐emulsion technique.

The encapsulation of pigment is achieved by mixing a surfactant‐stabilised pigment dispersions and a monomer/oligomer mini‐emulsions and subjecting both to mini‐emulsification conditions. A film of encapsulated pigment mini‐emulsion is finally UV cured using water‐soluble initiator. Efficient encapsulation is proven by ultra‐centrifugal sedimentation, scanning electron microscopy and thermogravimetric analysis (TGA). The stability of pigment dispersions and also the encapsulation process are investigated.

TGA and ultracentrifuge sedimentation results showed that CI Pigment Red 122 is successfully encapsulated into polyester acrylate/HDDA resins. The oligomer (polyester acrylate) in the presence of organic pigment could stabilise the mini‐emulsion droplets without introducing any other hydrophobes (co‐stabiliser) in the formulation. In addition, the encapsulation percentage and suspension stability of mini‐emulsion are best when the polyester acrylate/HDDA weight ratio is 3:2.

The UV‐curable resins used in the present context are 1,6 HDDA and polyester acrylate. Besides, various oligomer/monomer composition types could be used and its impact on encapsulation efficiency could be also studied.

This method of encapsulation is practically effective for modification of organic pigments for use in UV‐curable ink‐jet printing inks.

The developed method is novel from a literature point of view and can be of a great benefit to achieve the required properties of pigmented UV‐curable system in inkjet printing of textiles. In addition, it could find numerous applications in surface coating.

UV curing technology has a number of unique advantages over the conventional curing technologies. However, until very recently, there had been few successful examples of the application of UV curing technology in ink‐jet printing. Several reasons, including the requirement of low viscosity for ink‐jet printing inks, were responsible for the lack of development of UV curable ink‐jet printing inks. This paper describes, in some details, the challenges that a formulator had to face in developing UV curable ink‐jet printing inks, together with information on the status quo of UV curable ink‐jet printing technology.

The purpose of this paper is to synthesise UV curable emulsion latex and to study characteristics and various performance properties such as tackiness, peel adhesion and cohesive strength for pressure sensitive adhesive (PSA) application after UV curing.

The two component water‐based ultraviolet (UV) curable acrylate PSAs were synthesised by emulsion copolymerization. The synthesised emulsion samples were characterised and various performance properties such as tackiness, peel adhesion and cohesive strength for PSAs were tested after UV curing.

The thermal analysis showed the effect of methyl methacrylate (MMA) content on the glass transition temperature of emulsions, which had significant effect on tack. Effects of varying concentration of multifunctional monomer trimethylolpropane triacrylate (TMPTA) and UV exposure time on properties of UV curable PSA were also studied.

The results associated with the UV curable water based PSA has certain advantages, such as low VOC and fast curing rate and with the scope for further research by using the radiations with different intensities or other radiation systems such as electron beam curing.

Practically the UV water based PSAs are already in industrial use for glass lamination, silicon semiconductor dicing, and in medical use for band aids and drug delivery systems and for dental applications for cavity filling.

The water based UV curable PSA synthesised by emulsion polymerization had very good tackiness properties with lower MMA content. It was observed that the lower the concentration of TMPTA, the better the performance properties, such as tack and peel strength. It was also observed that with increasing TMPTA concentration the cohesive strength increased.

Epoxy acrylate which is commercially utilized for UV curable coatings although has excellent adhesion, flexibility, hardness and chemical resistance, they lack in antimicrobial properties. Citric acid (CA) is economical as well as a bio-based compound which possess an antimicrobial activity. So, the purpose of this research investigation is the preparation of CA-based oligomer which can be further incorporated with epoxy acrylate and tri (propylene glycol) Diacrylate (TPGDA) to form uv curable coating and the study of its antimicrobial property.

A UV-curable unsaturated oligomer (CUV) was synthesized from CA and glycidyl methacrylate (GMA). The chemical structure of CUV was confirmed by FTIR, ¹H NMR, GPC, hydroxyl value, acid value and iodine value. Further, CUV was assimilated as an antimicrobial as well as crosslinking agent to copolymerize with epoxy acrylate oligomer and a series of UV-cured antimicrobial coatings were concocted by employing UV-curing machine. The consequence of varying the fraction of CUV on the mechanical, chemical, thermal and antimicrobial properties of UV-cured wood coatings was explored.

Results exhibited good mechanical, chemical and thermal properties. In addition, it was perceived that the zone of inhibition against S. aureus got enlarged with increasing content of CUV in the coating formulation.

The synthesized bio-based CUV reveals an extensive potential to ameliorate the antimicrobial properties of UV-curable coatings.

In order to manufacture scaffolds for tissue engineering, a dynamic mask rapid prototyping system to cure UV‐curable biodegradable material was developed. The aim of this paper is to document this system.

A digital micro‐mirror device (DMD) was used as the dynamic mask generator, with each layer's mask pattern dictated by our self‐developed software. To build the scaffolds, UV light reflected by the DMD was then focused onto the biodegradable material to cure it. The biodegradable material used in this experiment was a mixture of 85/15 PLGA, PEG‐HEMA, and a photo‐initiator.

The dynamic mask rapid prototyping system was successfully built and scaffolds made of UV‐curable biodegradable material were fabricated to verify the system capacity. The working exposure time for each layer was 45 s except for the first layer, which was 60 s. Scaffolds with 0°/90° and 60°/120° strips in alternating layers were fabricated and the pore size error in X and Y axes of 0°/90° design was found to be 7.33 and 2.13 percent, respectively. Preliminary cell culture tests indicate the fabricated scaffold is not harmful to MG‐63 cell growth.

Different scaffold designs and more UV‐curable biodegradable materials may be further implemented and tested through this system.

This research developed a novel system for tissue engineering scaffold fabrication which can process UV‐curable biodegradable material.

The purpose of this paper is to prepare waterborne UV-curable pigment pastes for cotton fabric printing.

O/W (oligomer-in-water) emulsions of polyurethane acrylate (PUA) oligomer in sodium dodecyl benzene sulphonate (SDBS) aqueous solution were prepared by ultrasonic emulsification method.

The present work studies various factors affecting the stability and droplet size of the O/W emulsion stabilised by SDBS. The optimal emulsifier concentration was 2.5 per cent, under which condition the stability of the emulsion increased as the emulsifier content increased, with a subsequent decrease in the droplet size of the emulsion, while above which emulsion agglomeration occurred. Increasing the power and duration of ultrasonic dispersion resulted in increased emulsion stability and decreased droplet size, while increases in the oligomer content reduced the emulsion stability. Darocure 1173 mixed with PUA and then emulsified in the SDBS aqueous solution guaranteed uniform dispersion of the photoinitiator, resulting in faster curing speed.

This paper presents a new method for making waterborne externally emulsified oligomers for UV curing, and finds that it is easy to convert the existing oligomers into waterborne equivalents by this method. Cotton fabrics printed with the oligomer emulsion based pastes were found to have good colour strength and crockfastness.

Woven and knitted polyester fabrics were pretreated with formulations containing waterborne UV curable resins and silica particles to improve inkjet print quality. The selected formulations were applied with low add-on to reduce the adverse effect on fabric hand without sacrificing the print quality. A print pattern with block areas and lines in cyan, magenta, yellow, and black colors was designed and inkjet printed on the pretreated fabrics with a wide-format inkjet printer (Encad Novajet 750) to investigate the effects of the UV curable pretreatment on the inkjet print color qualities including color depth, color gamut and color lightness.

Experimental results show that both the color depth and gamut of prints on the pretreated taffeta and knitted polyester fabrics were enhanced compared to those on untreated polyester fabrics. However, both the color depth and gamut of the prints on the pretreated satin polyester fabrics were reduced. The lightness change of the inkjet printed colors on pretreated knitted fabrics is similar to that of untreated fabrics whereas the lightness change of prints on pretreated satin and taffeta fabrics shows some differences. All colors have increased lightness on pretreated satin fabrics. However, magenta and black have decreased lightness on the pretreated taffeta fabrics.

The purpose of this work was to perform a systematic study on the effect of formulation on the physical and mechanical properties of ultaviolet (UV) curable urethane acrylate resins. In addition, the authors wanted to derive mathematical formula for the prediction of physical and mechanical properties for the aforementioned system.

The experiments were carried out based on mixture experimental design to determine the effect of different multifunctional acrylates (i.e. 1,6-hexanediol diacrylate (HDDA), tripropylene glycol diacrylate (TPGDA), trimethyolpropane triactylate (TMPTA)) concentration on the physical and mechanical properties of a UV curable polyurethane acrylate system. The urethane oligomer was synthesized and characterized by the research team. Microhardness, adhesion strength and scratch resistance of the cured films were evaluated as the physical and mechanical properties.

The results revealed that the resin and TMPTA concentrations had the most significant effects on the microhardness property. Adhesion strength of the films showed a linear trend with respect to all variables. Moreover, all components also had a significant and complex influence on the scratch resistance of the cured systems. In addition, mathematical equations proposed by mixture experimental design were derived for all the mentioned properties.

Other multifunctional acrylate monomers (i.e. more than three functional) can be used in the formulations. The kinetics of the curing can affect on the network formation and consequently on the properties of the cured films.

The obtained results can be used by the researchers who are active in the field of structure-property relationship of polymers and surface coatings. The reported data and the mathematical equations can also be used for the formulating of an appropriate formulation based on a specific application.

A systematic and statistical-based approach, i.e. mixture experimental design, was used to evaluate the effect of formulation on some of the properties of a UV curable polyurethane acrylate system. A urethane oligomer and three different multifunctional acrylate monomers as reactive diluents were used in the formulations. Noteworthy to mention that several mathematical models were derived by using analysis of variance for the prediction of the properties studied in this system.