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To evaluate the photochromic performance of fulgide 1‐E with ferrocene in polymer matrices.

The fulgide 1‐E with ferrocene dye 2 doped in polymethylmethacrylate was prepared and the effects of UV irradiation were studied using spectrophotometer. The reversible reaction was effected using white light. The effect of heat was also determined.

A film of the brown coloured fulgide 1‐E with ferrocene doped in PMMA polymer was irradiated with ultraviolet light (365 nm), the film turned red. The later colour was partially switched back to the original brown colour when the film was irradiated with a white light. It was found that the rate constants of photocoloration reaction at initial stages are faster than those at late stages. Similarly, the photocoloration reaction was slower than the photobleaching reaction. Photocoloration reaction decreased with the increase of the annealing temperatures, but for photobleaching reaction, the rates were almost similar (at 46 and 82°C). The fatigue resistance of the film was greatly improved when the annealing temperature increased to 82°C.

The polymethylmethacrylate polymer doped photochromic fulgide 1‐E and ferrocene 2 described in the present paper was prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

The photochromic materials developed can be used for different applications, such as coatings and holography.

The method developed may be used to enhance the performance of photochromic materials.

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

The poly(methyl methacrylate) PMMA and epoxy resin doped with photochromic spirooxazine (SO) are prepared and the effects of ultraviolet (UV) irradiation are studied using spectrophotometer. The reversible reaction is effected using white light. Photochemical fatigue resistance of these films is also studied.

Irradiation of colourless 7′,8′‐dichloro‐1,3,3‐trimethylspiro[indoline‐2,3′‐[3H]benzo[b][1,4]oxazine] (SO) doped in PMMA and epoxy resin with UV light (366 nm) results in the formation of an intense purple‐red coloured zwitterionic photomerocyanine (PMC). The reverse reaction is photochemically induced by irradiation with white light. Photocolouration and photobleaching reactions follow a first‐order rate equation. It is found that photocoloration rate constant of (SO) in both matrices is almost the same, which is unexpected. On the other hand, the rate of photobleaching reaction of (PMC) in PMMA is twice slower than that in the epoxy resin. It seems that the presence of the two chlorine atoms at positions 7′ and 8′ of the benzooxazine moiety destabilise the PMC in epoxy resin film and results in speeding up the fading process compared to that in PMMA. SO doped in epoxy resin shows much better fatigue resistance than that doped in PMMA.

The PMMA and epoxy resin polymers doped photochromic spirobenzooxazine described in this paper were prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

The photochromic materials developed can be used for different applications, such as coatings and holography.

The method developed may be used to enhance the performance of photochromic materials.

This paper aims to study the combination of photochromic microcapsules, which use the ultraviolet (UV) rays for colour changing phenomena, and titanium oxide (TiO₂) nanoparticles (NPs), which block the UV rays by their photocatalytic activity in the sunlight on the cotton fabric.

The TiO₂ NPs mixed with photochromic printing paste are used for coating on cotton fabric and further curing is performed in a one-step process. The photochromic pigment printed fabric impregnated in a liquid solution is processed in a two-step process with two variables such as 1% TiO₂ and 2% TiO₂. The characterization of samples was done with a UV transmittance analyser, surface contact angle, antimicrobial test and fabric physical properties.

The UV protection of TiO₂-treated photochromic printed fabric was high and gives the ultraviolet protection factor rating of 2,000 which denotes almost maximum blocking of UV rays. The antibacterial activity of the one-step samples shows the highest 36 mm zone of inhibition (ZOI) against S. aureus (gram-positive) and 32 mm ZOI against E. coli (gram-negative) bacteria. The one-step sample shows the highest static water contact angle of 118.6° representing more hydrophobicity, whereas the untreated fabric is fully wetted (0.4°). In two-step processes, as the concentration of TiO₂ increased, the antibacterial activity, UV blocking and hydrophobicity became better.

This work achieves the multifunctional finishes by using photochromic microcapsules and NPs in a single process as a first attempt. The results inferred that one-step sample has achieved higher values in most of the tests conducted when compared to all other sample.

The paper aims to provide an overview of the area of smart textiles.

The paper describes and discusses new and developing materials and technologies used in the textile industries.

Significant progress has been achieved in the area of technical textiles. Fibres, yarns, fabrics and other structures with added‐value functionality have been successfully developed for technical and/or high performance end‐uses. The basic building blocks are already in place in the field of smart textiles and clothing.

As progress in science and engineering research advances, and as the gap between designers and scientists narrows, the area of smart clothing is likely to keep on expanding for the foreseeable future. Growth is predicted to occur in two distinct directions: performance‐driven smart clothing and fashion‐driven smart clothing. There are challenges that have to be addressed.

The paper provides information of value to those interested in the future directions of the textile industry.

The purpose of this paper is to evaluate the effect of antioxidant 2,6-di-tert-butyl-p-methylphenol (BHT) on the thermal stability and fatigue resistance of spirooxazine and then study the properties of photochromic polyvinyl butyral resin (PVB) films.

BHT was introduced into the spirooxazine system by blending and covalent bonding. The properties of spirooxazine solutions and photochromic PVB films were studied.

The thermal stability and fatigue resistance of spirooxazine covalently linked (BHT-SO) or mixed (BHT/SO) with BHT were higher than the system without BHT, and BHT-SO was the better one. But acidic substance would greatly impair the fatigue resistance of spirooxazine. The optimum addition amount of BHT-SO2 to PVB was 2.5 per cent, and the minimum limit was 0.01 per cent. The fading kinetic and fatigue resistance of film were similar to the solution and better. Plasticizer could accelerate the fading rate and strengthen the mechanical properties of photochromic film but had no effect on the fatigue resistance.

Spirooxazine could be grafted onto the PVB chain to make the ring closure fading reaction slower.

In addition to the wide application prospects of photochromic materials in decoration, optical storage, etc., the photochromic PVB film in the car safety glass can absorb sunlight and turn blue, then fade to colorless when the sunlight disappears, making the interior environment more comfortable.

The introduction of BHT into the spirooxazine system not only exerts its ability to capture free radicals, but its bulky volume also increases the resistance of the ring closure, making the fading process slower.

In this article, a unique concept for a device that conducts photochromic measurement in the reflectance mode together with the methodology described has been patented in the Czech Republic in the author's name. This unique device allows measurements of colorimetric and spectral characteristics of photochromic textiles as photochromic sensors and also as a fatigue tester for the control of color change stability. The measurement of colorimetric and spectral parameters in comparison together with the intensity of UV irradiation allows the dependence of color change on intensity of irradiation to determined, and a scale for individual visual observation to be developed, as well as the risks of UV irradiation to be evaluated.

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

The poly(methyl methacrylate) (PMMA) and epoxy resin doped with photochromic spirobenzopyran were prepared and the effects of ultraviolet (UV) irradiation were studied using spectrophotometer. The reversible reaction was effected using white light. Photochemical fatigue resistance of these films was also studied.

Irradiation of colourless 1′,3′,3′‐trimethyl‐6‐nitrospiro[2H‐1‐benzopyran‐2,2′‐indoline] spiropyran (SP) doped in PMMA and epoxy resin with UV light (366 nm) results in the formation of an intense purple‐red coloured zwitterionic photomerocyanine (PMC). The reverse reaction was photochemically induced by irradiation with white light. Photocolouration of SP doped in PMMA follows a first‐order rate equation (k=0.0011 s⁻¹), while that doped in epoxy resin deviates from linearity. It was found that photobleaching follows a first‐order equation in both matrices. The photobleaching rate constant of PMC in both matrices is the same and equals 0.0043 s⁻¹. Spirobenzopyran doped in PMMA shows better fatigue resistance than that doped in epoxy resin.

The PMMA and epoxy resin polymers doped with photochromic spirobenzopyran described in the present paper were prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

The photochromic materials developed can be used for different applications, such as coatings and holography.

The method developed may be used to enhance the performance of photochromic materials.

Our previous papers (Viková & Vik, 2005) described a unique device, now patented in the Czech Republic in the author's name, for photochromic measurement in a reflectance mode together with a methodology. This device allows photochromic sensors to test the colorimetric and spectral characteristics of photochromic textiles, and also fatigue tests for control of colour change stability. This concept of colorimetric and spectral parameters also finds the dependence of colour change on the intensity of UV irradiation and temperature. In this paper, we would like to describe the dependence of colour change on temperature for the photochromic Photopia AQ Ink system (Blue, Purple and Yellow) produced by Matsui Shikiso Chemical Co.Ltd.

It is known that the reversion of photochromic compounds from coloured to colourless is promoted thermally. The photochromic structure can achieve a lower level of saturated absorbance at higher temperatures when thermo reversible photochromic systems, such as spirooxazines and chromenes, increase the rate of thermal bleaching reaction and thus decrease light stimulated coloration.

To evaluate the photo, thermo, piezo and solvatochromism of new bis‐imidazole derived from three isomers of chlorobenzaldehyde.

The synthesis of the three new bis‐imidazoles was accomplished using modified procedure of the previously reported method, by dissolving the imidazol derivative and cooling in ice bath, and adding potassium ferricyanide drop wise. The compounds were used evaluate the effects of the position of the substitutions on the aromatic ring, on the photo, thermo and piezochromic properties.

New bis‐imidazole derived from 2‐chloro, 3‐chloro and 4‐chloro phenyl have been synthesised and their photochromic properties upon irradiation with ultraviolet light were studies in different solvents. The photochromic properties and performance were affected remarkably upon changing the solvent. Also, the thermochromic properties upon heating in different solvents were studied. The dimers showed piezochromism on grinding.

The method reported for the synthesis is simple. The new compounds showed photochromic, thermochromic, piezochromic, and solvatochromic making them potential candidates for many applications such as sensors, optical data storage and heat sensitive materials.

The method for preparation was modified and improved. The materials prepared were new compounds.