NEKE KARAKTERISTIKE TERMOKROMNIH BOJILA

Đurđica Parac-Osterman1, Ana Sutlović1, Martinia Ira Glogar1

1Sveučilište u Zagrebu Tekstilno-tehnološki fakultet, Prilaz baruna Filipovića 28, Zagreb, Hrvatska

Sažetak

Termokromna bojila se danas primjenjuju u nizu različitih proizvoda, od ambalaže, komercijalnog tiska, zaštitnih dokumenata, tekstila i dr. Karakteristika ovih bojila temelji se na mehanizmu inducirane reverzibilne promjene boje kemijskog spoja uzrokovane pucanjem kemijskih veza ili promjene molekularnih konformacija pri čemu dolazi do promjene između dva stanja koji se prati pojavom različitih apsorpcijskih spektara. Materijali sa svojstvom termokromizma spadaju u skupinu „pametnih materijala“ sa svojstvom osjeta okoline. Ispitivanja su provedena s trgovačkim bojilima PPG Industries iz kemijske skupine spirooksazina i spironaftooksazina. Metodom sitotiska na pamučnoj tkanini i Al foliji uzorci su zatim ispitivani u uređaju za detekciju termokromnih bojila (19 0C do 40 0C, u koraku od 0,5 0C ) i istovremeno spektrofotometrijski su se mjerile spektralne karakteristike boje. Na prikazanim histogramima potvrdila su se svojstva „zamora materijala“ i stabilnost bojila. Dokazano je da isto termokromno bojilo, otisnuto pod istim uvjetima, ima drugačije djelovanje ovisno o podlozi. Potvrđeno je da aktivnost bojila u umreženom sustavu polimernog vezivnog sredstva ovisi o veličini molekule kao i o prostornoj građi bojila. Dokazana je veća stabilnost zadržavanja tona boje na pamučnoj tkanini u odnosu na AL foliji. Potvrđuje se nužnost istraživanja utjecaja svake pojedine podloge u cilju određivanja termokromne aktivnosti svakog bojila.
Ključne riječi: termokromna bojila, „pametni materijala“ sitotiska, pamučna tkanina, Al folija, stabilnost bojila

SOME CHARACTERISTICS of THERMOCHROMIC DYES

Abstract

Thermochromic dyes are today used in a number of different products, from the packaging, commercial printing, document protection, textiles and others. The characteristic of these dyes is based on the mechanism of induced reversible color change of the chemical compound, caused by breakage of chemical bonds or changes in molecular conformation, in which there is a change between two states followed by appearance of different absorption spectra. Materials exhibiting thermochromic behavior belong to the group of "smart materials" with the capacity of sensing the environment. The analyses were performed with commercial PPG Industries dyes, belonging to chemical groups of spyrooxazine and spyronaftooxazine. The samples were prepared by the method of screen printing on cotton fabric and Al foil and were tested in a device for the detection of thermochromic dyes (19C to 40C, in the step of 0.5C) and at the same time the spectral characteristics of color were measured spectrophotometrically. On histograms presented, the properties of material fatigue and dyes stability have been confirmed. It was also proved that the same thermochromic dye, printed under the same conditions, has a different effect depending on the substrate. It was confirmed that the activity of colorants in a networked system of polymeric binder, depends on the size of the molecule as well as the spatial dye composition. It exhibits greater stability to keep the color hue on the cotton fabric in compare to the AL foil. The necessity of studying the impacts of each substrate in order to determine the activity of each thermochromic dyes, has been determined.
Key words: Thermochromic dyes, "smart materials", screen printing, cotton fabric, Al foil, stability dyes


Patrik Ervells latest collection is ironically titled “Software”ADIDAS ORIGINALS TUBULAR SHADOW. In the notes from the presentation, Ervell says he was interested in developing tension between nostalgia and sci-fi,NIKE ZOOM WINFLO 3 and even included 90s cyberpunk amongst his influences. Ervell developed this point of view by creating an imaginary software company called Idegen software systems. He then re-appropriated the company’AIR JORDAN XXXI MENs logo in several of the collection’s garments. Elsewhere,MBT TARIKI MEN mohair coats with oversized lapels made an appearance alongside mock neck tees,NIKE AIR JORDAN RETRO 5 police-inspired ribbed sweaters,MBT FORA GTX WOMEN flight bombers, and polyurethane leather coats. The setting was also suitably dystopian, and the resulting ambiance was something akin to if the creators of Deutschland 83 and Hackers met up and decided to create a collection… We mean that as a compliment.Yesterday afternoon,JORDAN CP3 IX MEN artist JR spent the day working on his latest collaborative piece with Daniel Arsham in Greenpoint,NIKE AIR MAX 90 Brooklyn,MBT KIMONDO GTX MEN NYC. Connecting the lines between art, architecture, dance and theater, Daniel Arsham has been known to subvert existing architectural structures in unconventional,NIKE CLASSIC CORTEZ NYLON playful ways; confusing and confounding the expectations of space and form. Source: Street Art News .