Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Potassium sulfate droplets and the origin of turbidity in alabaster glasses
KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
2006 (English)In: Glass Technology, ISSN 0017-1050, Vol. 47, no 1, 15-18 p.Article in journal (Refereed) Published
Abstract [en]

A study of the criteria required to manufacture multicomponent semi-transparent silicate glasses, so called 'alabaster' glasses, has found that the optical effect is caused by noncrystalline potassium sulfate droplets. The droplets were characterised by use of XRD, SEM/EDX and Raman spectroscopy. The size range of the particles is of the order of 5-50 micrometers. It was found that the droplets consisted of potassium sulfate, even if other sulfate compounds were added to the glass. The amount of sulfate compound added, the melting temperature of the furnace and the melting time have significant effects on the optical density of the glass. The optical density of the glass can be correlated to the calculated surface tension of the host glass, suggesting that phase separation of a sulfate enriched liquid phase is part of the mechanism forming the droplets. By adding pigments several different colours can be obtained, but the alabaster effect is not achieved during reducing conditions, thus it seems not possible to produce colours originating from reduced pigments. Pigments tested were Cr, Fe, Co, Cu, Au, Mo/Se, Nd and Ti/Ce/Se.

Place, publisher, year, edition, pages
2006. Vol. 47, no 1, 15-18 p.
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:kth:diva-16108ISI: 000241757700003Scopus ID: 2-s2.0-33745453337OAI: oai:DiVA.org:kth-16108DiVA: diva2:334150
Note
QC 20100820Available from: 2010-08-05 Created: 2010-08-05 Last updated: 2017-12-12Bibliographically approved
In thesis
1. Red Glass Coloration: a Colorimetric and Structural Study
Open this publication in new window or tab >>Red Glass Coloration: a Colorimetric and Structural Study
2006 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [sv]

Syftet med detta arbete har varit att försöka hitta alternativ till det kadmiumbase¬rade röda pigment som används idag. Detta har gjorts genom att delvis under¬söka kombinationer av grundämnen som i litteraturen finns omnämnda som röda glaspigment, delvis genom att försöka förbättra och underlätta produktionen av redan kända, men problematiska pigment.

Det har konstaterats att det går att framställa ett rött glas när man smälter soda¬kalkglas med en kombination av molybden och selen, under reducerande beting¬elser. Rött glas med denna kombination har inte rapporterats tidigare. Pigmentet är känsligt för vilken glassammansättning man använder och flera vanliga glas¬komponenter måste undvikas. För att utvärdera färgen hos glasen användes UV/vis-spektroskopi och färgkoordinater i CIE-systemet. Både ESCA- och XANES-analyser visar att molybden finns i glaset som Mo6+joner. Färgen upp¬kommer troligtvis genom en interaktion mellan molybdenjonerna och selen i reducerad form. UV/Vis- och XANES spektra visar att selen finns i glaset i redu¬cerad form.

Färgutvecklingen hos kopparrubinglas studerades med UV/vis-spektroskopi. Detta pigment behöver värmebehandlas för att färgen skall bildas. När låga vär¬mebehandlingstemperaturer och låga halter av de färgande komponenterna an¬vänds, är pigmentet stabilt under lång tid. Experimentella resultat från EXAFS- och TEM-analyser visar tydligt att färgkällan är metalliska kopparpartiklar i na¬nostorlek.

Inverkan av olika reduktionsmedel på guld- och kopparrubinpigmenten har un¬dersökts. Det konstaterades att SnO är mer reducerande gentemot koppar än Sb2O3 i sodakalkglas. Kopparrubinglas kan framställas med bara endera av dessa reduktionsmedel, men SnO ger bättre resultat. Skift i absorbanstoppens läge och provets färg har observerats hos både guld- och kopparrubiner. Det största skiftet finns hos glas där en blåaktig ton erhållits. Skiftet beror troligtvis på att större partik¬lar bildats.

Möjligheterna att kombinera röd färg med halvtransparenta alabasterglas har undersökts. Det konstaterades dock att alabastereffekten inte går att kombinera med pigment som kräver starkt reducerande miljöer.

Både guld- och kopparrubiner är miljövänligare än det kadmiumbaserade pig¬mentet, och måste anses som möjliga alternativ. Mo/Se-pigmentet kan också vara ett alternativ.

Abstract [en]

The aim of this thesis has been to find alternatives in the alkali silicate glass system to the most commonly used red glass pigment today, which is based on Cd(S, Se). The overall strategy has been to facilitate the use of already existing, well known but complicated and control-demanding pigments. Also the possi¬bilities to obtain red glass by combining elements as briefly reported in litera¬ture as possible red glass pigments, has been investigated.

It has been found that by combining molybdenum and selenium in alkali-lime-silica glass under reducing conditions, a red pigment can be obtained. Red glass originating from this combination has not been reported earlier. The pigment is sensitive to batch composition and some glass components must be avoided. UV/vis spec¬troscopy and CIE colour coordinates were used when colour of samples was evaluated. Both ESCA and XANES give evidence that molybde¬num is present as Mo6+ ions. The colour is caused by an interaction between the molybdenum ions and selenium under reducing conditions. The presence of se¬lenium in a reduced state is evidenced by UV/vis spectroscopy and XANES analysis.

The colour development in copper ruby glasses was studied by UV/vis spectros¬copy. It was observed that when low concentrations of colouring components were used, the pigment is stable regarding colour over long periods of time. Ex¬peri¬mental results from TEM and EXAFS provided good evidence that the col¬our origi¬nates from nanoparticles of metallic copper. This is in analogy with the gold ruby pigment.

The impact of different reducing agents on the copper and gold ruby pigments was examined. It was concluded that SnO has a stronger reducing capacity to¬wards copper than Sb2O3 in alkali silicate glasses. The copper ruby colour can be obtained by the use of one of these reducing agents solely. Shifts in absorbance peak position as well as in colour hues are observed in both pigments and the largest shifts in absorption are observed in blue or bluish glasses, probably caused by larger particles.

The possibility to combine red colour and semi-transparent alabaster glasses was studied. The studies however, indicated that the alabaster effect is not compati¬ble with pigments requiring strongly reducing conditions.

Both gold and copper rubies are more environmentally friendly than the cad¬mium based Cd(S, Se) pigment, and must be regarded as possible alternatives. The Mo/Se pigment can also be an alternative.

Place, publisher, year, edition, pages
Stockholm: KTH, 2006
Series
Trita-OOK, ISSN 0348-825X ; 1083
National Category
Organic Chemistry
Identifiers
urn:nbn:se:kth:diva-4176 (URN)91-7178-486-1 (ISBN)
Public defence
2006-12-01, Sal F3, KTH, Lindstedtsvägen 26, Stockholm, 13:00
Opponent
Supervisors
Note
QC 20100820Available from: 2006-11-22 Created: 2006-11-22 Last updated: 2010-08-20Bibliographically approved

Open Access in DiVA

No full text

Scopus

Search in DiVA

By author/editor
Bring, TorunKloo, Lars A.
By organisation
Inorganic Chemistry
In the same journal
Glass Technology
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 128 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf