274 research outputs found
Inkjet Printing in Liquid Media: Intra-Volumetric Drop Coalescence in Polymers
The tendency to develop flexible and transparent materials has been growing in the last decade. As inkjet printing technology has become a widespread method for the fabrication of functional materials, the investigation of the inkjet printing process seems to be essential with regard to polymers, which are a viscous and flexible media. In this study, we evaluated the dependence of ink drop coalescence on process parameters such as polymer viscosity (controlled by polymerization time), drop spacing and drop speed. The results showed that drop coalescence was mostly influenced by drop speed, while drop spacing and substrate polymer viscosity did not significantly affect the printing results. The presented data are crucial for understanding the processes involved in the fabrication of flexible materials by inkjet printing
Reversible sol-gel-sol medium for enzymatic optical biosensors
In this paper we for the first time report a reversible sol-gel-sol approach to obtain optical enzymatic biosensors with improved enzyme stability and good sensitivity by using desktop inkjet printing. The developed technique is based on the bio-inorganic inks allowing for a sol-gel-sol transition of the inorganic matrix: from liquid ink to solid alumina matrix with entrapped enzymes and subsequent color response due to enzymatic reaction upon the resuspension of the matrix. This approach improves the stability of the biomarkers entrapped in the porous inorganic matrix, and at the same time maintains a high sensitivity of the biomolecules, which facile release is ensured by the gel-sol transition. Rheological parameters of the developed bio-inorganic ink are highly adjustable making it suitable for the deposition on different surfaces by inkjet printing. The potential and utility of this approach is demonstrated by a successful production of optical biosensors for glucose and uric acid.\u3cbr/\u3e\u3cbr/\u3
Inkjet printing of TiO2/AlOOH heterostructures for the formation of interference color images with high optical visibility
This paper describes a practical approach for the fabrication of highly visible interference color images using sol-gel ink technique and a common desktop inkjet printer. We show the potential of titania-boehmite inks for the production of optical heterostructures on various surfaces, which after drying on air produce optical solid layers with low and high refractive index. The optical properties of the surface heterostructures were adjusted following the principles of antireflection coating resulting in the enhancement of the interference color optical visibility of the prints by as much as 32%. Finally, the presented technique was optimized following the insights into the mechanisms of the drop-surface interactions and the drop-on-surface coalescence to make it suitable for the production of even thickness coatings suitable for printing at a large scale. We propose that the technology described herein is a promising new green and sustainable approach for color printing
Inkjet printing of TiO\u3csub\u3e2\u3c/sub\u3e/AlOOH heterostructures for the formation of interference color images with high optical visibility
\u3cp\u3eThis paper describes a practical approach for the fabrication of highly visible interference color images using sol-gel ink technique and a common desktop inkjet printer. We show the potential of titania-boehmite inks for the production of optical heterostructures on various surfaces, which after drying on air produce optical solid layers with low and high refractive index. The optical properties of the surface heterostructures were adjusted following the principles of antireflection coating resulting in the enhancement of the interference color optical visibility of the prints by as much as 32%. Finally, the presented technique was optimized following the insights into the mechanisms of the drop-surface interactions and the drop-on-surface coalescence to make it suitable for the production of even thickness coatings suitable for printing at a large scale. We propose that the technology described herein is a promising new green and sustainable approach for color printing.\u3c/p\u3
Inkjet Color Printing by Interference Nanostructures
Color
printing technology is developing rapidly; in less than 40
years, it moved from dot matrix printers with an ink-soaked cloth
ribbon to 3D printers used to make three-dimensional color objects.
Nevertheless, what remained unchanged over this time is the fact that
in each case, dye inks (CMYK or RGB color schemes) were exclusively
used for coloring, which inevitably limits the technological possibilities
and color reproduction. As a next step in printing color images and
storing information, we propose the technology of producing optical
nanostructures. In this paper, we report use of inkjet technology
to create colored interference layers with high accuracy without the
need for high-temperature fixing. This was made possible due to using
titania-based colloidal ink yielding monolithic coatings with a high
refractive index (2.00 ± 0.08 over the entire visible range)
when naturally dried. By controlling the film thickness by using inkjet
deposition, we produced images based on controlled interference and
implementing color printing with one ink. The lack of dyes in the
proposed method has good environmental prospects, because applied
systems based on a crystalline anatase sol are nontoxic and biologically
inert. The paper explains in detail the principle of producing interference
images by the classical inkjet method and shows the advantages of
this technique in depositing coatings with uniform thickness, which
are required for large-scale interference color imaging even on unprepared
polymer films. This article demonstrates the possibility of inkjet
printing of nanostructures with a precision in thickness of up to
50 nm, we believe that the proposed approach will be the groundwork
for developing interference color printing approach and allow to implement
new methods of forming optical nano-objects by widely available techniques
UV-curable hybrid organic-inorganic composite inks with a high refractive index for printing interference images and holograms
Herein we report a new, facile and inexpensive methodology for obtaining highly refractive polymers suitable for inkjet printing using hexacoordinated titanium complexes (THC) and a UV-curable lacquer based on triethylene glycol dimethacrylate (TGD) that is a cheap and non-toxic monomer that can be rapidly polymerized under UV irradiation under ambient conditions. The resulting polymeric materials are characterized by a refractive index (RI) of about 1.85 in the solid state and have rheological properties suitable for inkjet printing applications. The polymeric materials can be printed onto solid supports resulting in surface structures giving rise to interference images and masking of rainbow holograms illustrating thus the prospective practical applications of the described approach
UV-curable hybrid organic-inorganic composite inks with a high refractive index for printing interference images and holograms
\u3cp\u3eHerein we report a new, facile and inexpensive methodology for obtaining highly refractive polymers suitable for inkjet printing using hexacoordinated titanium complexes (THC) and a UV-curable lacquer based on triethylene glycol dimethacrylate (TGD) that is a cheap and non-toxic monomer that can be rapidly polymerized under UV irradiation under ambient conditions. The resulting polymeric materials are characterized by a refractive index (RI) of about 1.85 in the solid state and have rheological properties suitable for inkjet printing applications. The polymeric materials can be printed onto solid supports resulting in surface structures giving rise to interference images and masking of rainbow holograms illustrating thus the prospective practical applications of the described approach.\u3c/p\u3
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