Increasing regulatory scrutiny and concerns over PFAS persistence have intensified the demand for high performance, fluorine free glass coatings to replace conventional PFAS based systems (ECHA, 2025). Silicone based materials are particularly well suited as PFAS alternatives due to their intrinsically low surface energy, excellent thermal and UV stability, and strong affinity for glass substrates through siloxane bond formation (Cheng, et al., 2025) (Jeevajothi, Subasri, & Soma Raju, 2013). The flexible Si–O–Si backbone enables effective stress dissipation under mechanical abrasion while maintaining durable hydrophobicity. In addition, silicone chemistries offer high formulation versatility, scalable processing, and compliance with emerging environmental and regulatory concerns (Qiu, et al., 2022) (Xiao, et al., 2024) (Taliantzis & Ellinas, 2025). Momentive Performance Materials has been actively developing a new line of non fluorinated silicone-based hydrophobic glass coatings for consumer electronics and automotive applications, covering material design, synthesis, formulation, and performance evaluation.

A systematic development framework was established, covering Silane/Siloxane/Resin chemistry selection, catalyst systems, curing behavior, mechanical durability, and hydrophobic stability under harsh conditions. Various hybrid material architectures were investigated to achieve an optimal balance between surface hydrophobicity, mechanical flexibility, and crosslink rigidity. The coatings were applied using scalable techniques- including PVD, flow, spray, and cloth wipe coating, followed by thermal curing from ambient temperature up to 150 °C. Comprehensive characterization involving water contact angle measurements, neutral salt spray, steel wool abrasion, chemical resistance, and weathering tests, evaluated coating endurance and hydrophobic retention. These newly developed silicone-based hydrophobic coatings consistently exhibited initial water contact angles above 100° and retained values greater than 95° after 3000 abrasion cycles, demonstrating robust siloxane network integrity and effective stress dissipation. Overall, these results validate that fluorine free silicone-based coatings can deliver hydrophobic performance and mechanical durability comparable to conventional PFAS systems while offering clear environmental and regulatory advantages.

The field of optical devices has seen increasing demand for improved performance of optical thin films in recent years. Controlling the refractive index of optical thin films by reducing the packing density of the film can improve the optical characteristics of optical devices. By gradually modulating the refractive index, unwanted spectral characteristics in optical multilayer filters can be minimized. Furthermore, gradually reducing the refractive index from the substrate to air enables the design of effective wide-angle antireflection coatings.

We developed a combined deposition system capable of simultaneously performing sputtering and electron-beam (EB) evaporation, although the vacuum levels required for these methods differ by three orders of magnitude. Optical thin films prepared by simultaneous sputtering and EB evaporation exhibit reduced refractive indices due to the decreased packing density of the film.

In this study, we used this deposition system to fabricate ultra-low-refractive-index SiO2 optical thin films with sufficient mechanical durability for practical applications.

SiO2 optical thin films were fabricated by the simultaneous deposition of direct-current pulse sputtering and EB evaporation. N-BK7 (Schott) and S-TIH11 (OHARA) were used as substrates. SiO2 (SUSONITY JAPAN G.K) was used as the evaporation material, and a Si sputtering target (USTRON, 4N) was employed for deposition. The substrate temperature was set to 100 °C, the deposition vacuum was 9.8 × 10-1 Pa, and the sputtering power was set to 1000 W to reduce the refractive index. During simultaneous deposition, the deposition rate of SiO2 on the sputtering side was 0.6 Å/s, while that on the EB evaporation side was 5.6 Å/s.

The spectral reflectance of the films was measured using a microscope spectrometer (USPM-RU III, Olympus). The refractive index at a wavelength of 550 nm was calculated using the Sellmeier dispersion formula derived from the refractive index of the film at the peak wavelength. The adhesion of the thin films was evaluated by a crosshatch test in accordance with ISO 9211-4.

The refractive indices of the films calculated from samples deposited on each substrate ranged from 1.17 to 1.19. Therefore, SiO2 optical thin films with a refractive index of 1.17 were successfully fabricated. No delamination was observed at the edges of the films in the crosshatch test. These results demonstrate that ultra-low-refractive-index SiO2 optical thin films with high adhesion can be fabricated using this deposition system.

Glass ion exchange has grown from a captivating laboratory process beginning in the 1960’s to an

indispensable industrial asset reliably increasing the performance of glasses across a wide range of

applications from tech to transportation1. Ion exchange in molten salt baths is a process however

hindered by physical limitations arising from the nature of salt baths themselves. Within the framework of a ZIM project, the TU Berlin and AMSTOG GmbH have developed a novel method for ion exchange of glass utilizing a dip-coating to allow for new and more flexible ion exchange possibilities which circumvents the limitations posed by traditional salt baths.

This method involves first coating the glass in the selected ion exchange medium whereupon the glass

is brought into a kiln in which the ion exchange takes place. Originally conceptualized as an alternative to salt baths for KNO3 hardening of thin glasses (<550μm), this crucial difference in processing effectively allows the high thermal inertia of the molten salt to be overcome, enabling much accelerated temperature manipulation during the ion exchange. This, and the nature of the coating medium serve to greatly extend general flexibility and allow application-specific tuning of the medium such as its viscosity, coating thickness, salt makeup and content.

Immersion challenges and uneven heating/exchange associated with ultra-thin glasses and salt baths

can also be effectively circumvented as we demonstrate the successful hardening of 20×20 cm panels

of 70 μm, 110μm, and 145μm thick glasses. In terms of hardening, the medium exceeds traditional salt

baths in terms of reliability while closely matching its degree of strengthening as shown in figure 1.

Multicomponent salts can be implemented alongside temperature manipulation be used to create

engineered stress profiles in glass in only one ion-exchange step. The dip-coating process affords new

flexibility to an established and reliable method for altering the properties glass.

The transition toward environmentally sustainable surface finishing technologies has driven significant interest in coating systems with reduced environmental impact and improved resource efficiency. Acrylic resin–based coatings are widely used for glass and polymer substrates due to their excellent transparency, weather resistance, and mechanical durability. However, conventional solvent-borne formulations can lead to increased volatile organic compound (VOC) emissions and a higher environmental burden.

This work presents recent developments in sustainable coating processes based on waterborne and high solids acrylic resin systems designed for application on polymer substrates such as polyethylene terephthalate (PET), acrylonitrile–butadiene–styrene (ABS), polypropylene (PP), and polycarbonate (PC). Several case studies of coating formulations for primer and topcoat applications are presented to illustrate these strategies. Emphasis is placed on formulation approaches that reduce solvent content and enable low temperature curing, while maintaining desirable coating performance, including good adhesion, optical properties, and surface hardness.

These findings highlight the potential of sustainable Domacryl, Domemul and Domopur acrylic and acryl modified polymer technologies for coating applications and contribute to the development of environmentally responsible coating processes for glass and plastic substrates.