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There is a rising demand for high-performance 3D printed objects that have established potential applications in the sector of dental, automotive, electronics, aerospace, etc. Thus, to meet the requirements of high-performance 3D printed objects, this study has synthesized, formulated and applied a resorcinol epoxy acrylate (REA) oligomer to a stereolithography (SLA) 3D printer.

Different formulations were developed by blending reactive diluents in the concentration of 10%, 15% and 20%, along with the fixed quantity of photo-initiators in the REA oligomer. The structure of synthesized REA oligomer was confirmed using 13 C nuclear magnetic resonance (NMR) and 1H NMR spectroscopy, and the rheological properties for prepared REA formulations were also evaluated. The ultraviolet (UV)-cured specimens of all REA formulations were thoroughly examined based on physical, chemical, optical, mechanical and thermal properties. The best suitable formulation was selected for SLA 3D printing.

As perceived, UV cured REA specimens exhibit superior mechanical, chemical and thermal properties, portraying the ability to use as a high-performance material. The increase in the concentration of reactive diluents indicated a significant improvement in the properties of REA resin. The 20% diluted formulation achieved excellent compatibility with a SLA 3D printer; thus, 3D objects are cast with good dimensional stability and printability.

Resorcinol-based resins have always been a key additive used to enhance properties in the coating and tire industry. In a new attempt UV, curable REA has been applied to a SLA 3D printer to cast high-performance 3D printed objects.

In this paper the types of screen printing inks available for curing by ultra‐violet light are described. A comparison is made with conventional thermally cured inks and the author asserts that the current drive towards energy conservation and reduction in atmospheric pollution has been a powerful stimulus to the development of UV cured inks. The cost effectiveness of these inks is examined by reference to the energy required, operational costs, equipment, the ink itself and reject rates.

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.

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.

The purpose of this work was to develop a new trispiperazido phosphate-based reactive diluent (diphosphate-piperazine hydroxyl acrylate [DPHA]) and used as a flame retardant with an epoxy acrylate (EA) in ultraviolet (UV)-curable wood coating.

The concentration of reactive diluent was varied from 0% to 20% in the UV-curable formulation with constant photoinitiator concentration. The effect of DPHA concentration on film properties was studied by differential scanning calorimetry and thermogravimetric analysis, gel content, water absorption and limiting oxygen index.

The results showed that the viscosity of the prepared formulation decreased by increasing reactive diluent (DPHA) concentration which leads to improving the coating efficiency. A high concentration of reactive diluent (DPHA) of the cured films shows good resistance against stain, mechanical and thermal properties, which results in an increased glass transition temperature (T_g) and cross-linking density of the films.

The new trispiperazido phosphate-based reactive diluent was used in wood coating formulation, which resulted in excellent flame-retardant properties with higher cross-linked density with good stain resistance. This material can provide a wide range of application for coating industries to produce a glossy finish.

This paper aims to investigate the effects on material performance in the epoxy acrylate resin system owing to the existence of the different ring of the cyclic methacrylate. In this paper, cyclic methacrylate as diluents was added into epoxy acrylate (EA) resin by ultraviolet (UV)-cured polymerization to investigate the effects on material performance owing to the existence of the different rings.

EA and 1-adamantyl methacrylate were synthesized by traditional methods according to previous papers, respectively. After adding different cyclic methacrylate as diluents to the EA oligomers, the system was exposed to the UV-light for polymerization.

The hydrophobic properties of the cured materials were increased slightly because of the alkyl groups from the methacrylate. The thermal stabilities and mechanical properties of the resins were enhanced by the cyclic diluents with the hard segments. Meanwhile, the crosslink density of the polymer decreased with the bulky group like adamantly owing to its huge structure.

The cyclic methacrylates were introduced into EA oligomers for decreasing the viscosity and increasing the materials performances, which could be recognized as new diluents applied in UV-cued polymerization.

The results of this study will be conducive to fabricate EA resins possessed with high thermal stabilities and mechanical properties by convenient UV-cured polymerization.

Describes the use of a new type of UV cured coating and adhesive which are not adversely affected by fluorescing agents, so that increased quantities of fluorescing agents can be employed without retarding the depth of cure. Therefore, UV cured coatings and adhesives with this enhanced fluorescent response can readily be observed by the human eye using “black light” or by an on‐line electro‐optical device for quality control analysis of each electronic assembly.

Resin jetting with piezo print‐heads is in increasing use, and in the rapid prototyping industry, the merging quality between adjacent droplets will determine the mechanical properties and reliability of the products. Therefore, it is essential to find an experimental technique to ensure seamless inter‐droplet merging. Speckle interferometry with electron microscopy (SIEM) is a micro‐mechanics measurement technique that has a spatial resolution approaching a few nanometers. In this paper, SIEM is successfully applied to measure the ultimate tensile stress and tensile modulus of jetted, UV‐cured cationic resin microsamples. Results show that the microsamples exhibit similar properties to the bulk material properties and that jetting two layers on top of each other is not detrimental to the material properties.

New acrylic and allylic resins were prepared by functionalising perfluoropolyethers chains, which assured peculiar surface properties. Blends having a different amount of the acrylic and of the allylic systems were cured in air by UV irradiation. The cure of the films was found dependent on the ratio between the two resins; the concentration for the obtaining of a film fully cured in air was determined. On the basis of this concentration, a macromer functionalised with the right amount of both the acrylic group and the allylic one was synthesised.

The development of UV curing technology has introduced new solder masks which will replace the thermally‐cured masks of the past. In doing so, processing efficiency will be increased in terms of time, energy and space saving. In considering the effective use of the new technology, thought must be given to many factors which influence the optimum performance of UV cured solder masks. The thickness of deposit will most certainly be greatly influenced by the choice of screen fabric, mesh size and squeegee which will subsequently impact upon the rate and extent of cure. One must also prepare the substrate surface adequately to compensate for the minimal wet adhesion and dwell time of a solventless ink prior to cure. Other factors such as flux chemistry, solder temperature, and soldering conditions play an important part in the performance of a solder mask and are discussed in detail. This paper was originally presented at the First Printed Circuit World Convention held at the Cafe Royal, London, in June, 1978.