Plasmonic Effect, Nano Particles of Gold, Silver, Copper and Best possible colorant

[Mustafa Umut Sarac]

Mustafa Umut Sarac submitted a new resource:

(there was a url link here which no longer exists) - Plasmonic Effect, Nano Particles of Gold, Silver, Copper and Best possible colorant

Silver, gold, and copper colloids have been the major focus of interest because of their unique optical properties
determined by the collective oscillations of electron density termed plasmons, which give rise to an intense absorption
in the near UV–visible. Such strong absorption induces the brilliant color of these metal nanoparticles in colloidal
dispersion. It is produced by the strong coupling of nanoparticles to the electromagnetic radiation of incident light,
leading to a...

(there was a url link here which no longer exists)

 

[Mustafa Umut Sarac]

Alsa Nanoparticle Colors

 

[cliveh]

:confused:

 

[Mustafa Umut Sarac]

Zsolnay Silver Copper Nanoparticle Colors

 

[Mustafa Umut Sarac]

Nanoparticles in Tiffany Glass

 

[Mustafa Umut Sarac]

Collodial Gold



History

Known since ancient times, the synthesis of colloidal gold was originally used as a method of staining glass. Modern scientific evaluation of colloidal gold did not begin until Michael Faraday's work of the 1850s.[8][9] A so-called Elixir of Life, a potion made from gold, was discussed, if not actually manufactured, in ancient times. Colloidal gold has been used since Ancient Roman times to colour glass intense shades of yellow, red, or mauve, depending on the concentration of gold, and in Hindu Chemistry, for various potions. In the 16th century, the alchemist Paracelsus claimed to have created a potion called Aurum Potabile (Latin: potable gold). In the 17th century the glass-colouring process was refined by Andreus Cassius and Johann Kunckel. In 1842, John Herschel invented a photographic process called Chrysotype (from the Greek word for gold) that used colloidal gold to record images on paper. Paracelsus' work is known to have inspired Michael Faraday to prepare the first pure sample of colloidal gold, which he called 'activated gold', in 1857. He used phosphorus to reduce a solution of gold chloride.

For a long time the composition of the Cassius ruby-gold was unclear. Several chemists suspected it to be a gold tin compound, due to its preparation.[10][11] Faraday was the first to recognize that the color was due to the minute size of the gold particles.[12] In 1898 Richard Adolf Zsigmondy prepared the first colloidal gold in diluted solution.[13] Apart from Zsigmondy, Theodor Svedberg, who invented ultracentrifugation, and Gustav Mie, who provided the theory for scattering and absorption by spherical particles, were also interested in understanding synthesis and properties of colloidal gold.[7][14]
[edit]
Synthesis

Generally, gold nanoparticles are produced in a liquid ("liquid chemical methods") by reduction of chloroauric acid (H[AuCl4]), although more advanced and precise methods do exist. After dissolving H[AuCl4], the solution is rapidly stirred while a reducing agent is added. This causes Au3+ ions to be reduced to neutral gold atoms. As more and more of these gold atoms form, the solution becomes supersaturated, and gold gradually starts to precipitate in the form of sub-nanometer particles. The rest of the gold atoms that form stick to the existing particles, and, if the solution is stirred vigorously enough, the particles will be fairly uniform in size.

To prevent the particles from aggregating, some sort of stabilizing agent that sticks to the nanoparticle surface is usually added. They can be functionalized with various organic ligands to create organic-inorganic hybrids with advanced functionality.[8] It can also be synthesised by laser ablation.
[edit]
Turkevich method

The method pioneered by J. Turkevich et al. in 1951 [15][16] and refined by G. Frens in 1970s,[17][18] is the simplest one available. Generally, it is used to produce modestly monodisperse spherical gold nanoparticles suspended in water of around 10–20 nm in diameter. Larger particles can be produced, but this comes at the cost of monodispersity and shape. It involves the reaction of small amounts of hot chlorauric acid with small amounts of sodium citrate solution. The colloidal gold will form because the citrate ions act as both a reducing agent, and a capping agent.

Recently, the evolution of the spherical gold nanoparticles in the Turkevich reaction has been elucidated. Interestingly, extensive networks of gold nanowires are formed as a transient intermediate. These gold nanowires are responsible for the dark appearance of the reaction solution before it turns ruby-red.[19]

To produce larger particles, less sodium citrate should be added (possibly down to 0.05%, after which there simply would not be enough to reduce all the gold). The reduction in the amount of sodium citrate will reduce the amount of the citrate ions available for stabilizing the particles, and this will cause the small particles to aggregate into bigger ones (until the total surface area of all particles becomes small enough to be covered by the existing citrate ions).
[edit]
Brust method

This method was discovered by Brust and Schiffrin in early 1990s,[20] and can be used to produce gold nanoparticles in organic liquids that are normally not miscible with water (like toluene). It involves the reaction of a chlorauric acid solution with tetraoctylammonium bromide (TOAB) solution in toluene and sodium borohydride as an anti-coagulant and a reducing agent, respectively.

Here, the gold nanoparticles will be around 5–6 nm.[21] NaBH4 is the reducing agent, and TOAB is both the phase transfer catalyst and the stabilizing agent.

It is important to note that TOAB does not bind to the gold nanoparticles particularly strongly, so the solution will aggregate gradually over the course of approximately two weeks. To prevent this, one can add a stronger binding agent, like a thiol (in particular, alkanethiols), which will bind to gold, producing a near-permanent solution. Alkanethiol protected gold nanoparticles can be precipitated and then redissolved. Some of the phase transfer agent may remain bound to the purified nanoparticles, this may affect physical properties such as solubility. In order to remove as much of this agent as possible the nanoparticles must be further purified by soxhlet extraction.
[edit]
Perrault Method

This approach, discovered by Perrault and Chan in 2009,[22] uses hydroquinone to reduce HAuCl4 in an aqueous solution that contains gold nanoparticle seeds. This seed-based method of synthesis is similar to that used in photographic film development, in which silver grains within the film grow through addition of reduced silver onto their surface. Similarly, gold nanoparticles can act in conjunction with hydroquinone to catalyze reduction of ionic gold onto their surface. The presence of a stabilizer such as citrate results in controlled particle growth. Typically, the nanoparticle seeds are produced using the citrate method. The hydroquinone method complements that of Frens,[17][18] as it extends the range of monodispersed spherical particle sizes that can be produced. Whereas the Frens method is ideal for particles of 12-20 nm, the hydroquinone method can produce particles of at least 30-250 nm.
[edit]
Sonolysis

Another method for the experimental generation of gold particles is by sonolysis. In one such process based on ultrasound, the reaction of an aqueous solution of HAuCl4 with glucose,[23] the reducing agents are hydroxyl radicals and sugar pyrolysis radicals (forming at the interfacial region between the collapsing cavities and the bulk water) and the morphology obtained is that of nanoribbons with width 30 -50 nm and length of several micrometers. These ribbons are very flexible and can bend with angles larger than 90°. When glucose is replaced by cyclodextrin (a glucose oligomer) only spherical gold particles are obtained suggesting that glucose is essential in directing the morphology towards a ribbon.
[edit]
Block Copolymer-mediated Method

An economical, environmentally benign and fast synthesis methodology for gold nanoparticles using block copolymer has been developed by Sakai et al. [3]. In this synthesis methodology, block copolymer plays the dual role of a reducing agent as well as a stabilizing agent. The formation of gold nanoparticles comprises three main steps: reduction of gold salt ion by block copolymers in the solution and formation of gold clusters, adsorption of block copolymers on gold clusters and further reduction of gold salt ions on the surfaces of these gold clusters for the growth of gold particles in steps, and finally its stabilization by block copolymers. But this method usually has a limited yield (nanoparticle concentration) which does not increase with the increase in the gold salt concentration. Recently, Ray et al. demonstrated that the presence of an additional reductant (trisodium citrate) in 1:1 molar ratio with gold salt enhances the yield by manyfold [4].

 

[Mustafa Umut Sarac]

Colloidal Silver

Ag nanoparticles are easily prepared by conventional
chemical reduction methods. The citrate (Turkevich
method) [229, 255, 256] and NaBH4 [255, 257–259] reduction
method are the two standard chemical preparation
routes. The synthesis of silver nanoparticles in AOT reverse
micelles by mixing AOT reverse micellar solutions at the
same water content containing Ag(AOT) and N2H4 or
NaBH4 offers a stable Ag colloidal solution and facile control
of particle size [260]. Following the treatment by a
size-selected precipitation process, nearly monodispersed Ag
nanoparticles are accessible [261, 262]. Shape-controllable
synthesis is always a challenging subject in nanoparticle
preparation. This is, without exception, for the synthesis of
silver nanoparticles. An amazing result of the shape control
of Ag nanoparticles was reported by Mirkin and co-workers
recently [263]. In the presence of bis(p–sulfonatophenyl)
phenyl–phosphine dihydrate dipotassium salt (BSPP) (as a
stabilizing agent), they observed that large quantities of
silver nanoprisms evolve from the initial spherical nanoparticles
through the fluorescent light irradiation. The
production of Ag nanoprisms lies in the light-induced ripening
process in which the small nanoprisms act as seeds, and
then grow as the small spherical nanocrystals are digested, as
shown in Figure 2. Most recently, one arresting experiment
shows that triangular Ag nanoprisms are obtained by boiling
AgNO3 in N,N–dimethyl formamide (a powerful reducing
agent against Ag+ ions) in the presence of PVP [264]. The
optimal experimental conditions are chosen ([AgNO3 =
0022 M, [PVP = 006 mM) so that a large population of
(mainly) triangular, and in general polygonal, nanoprisms
are formed in solution. Another attractive experiment shows
that truncated triangular Ag nanoplates can be synthesized
in large quantities through a seed-mediated growth (by
reduction of Ag+ ions with ascorbic acid on silver seeds
in a basic solution) in the presence of highly concentrated
micelles of CTAB [115, 265]. It is noticeable that, in these
cases, the optical properties of Ag nanoprisms or triangular
nanoplates varied in contrast to that of spheroidal Ag nanoparticles.
An intensive in-plane dipole resonance absorption
peaks at 550–675 nm, which gives a red- or blue-colored
colloidal solution. Another breakthrough in the shape control
of Ag nanoparticles was achieved by Xia and co-workers
[266]. They fabricated monodisperse Ag nanocubes in large
quantities by reducing silver nitrate with ethylene glycol in
the presence of PVP. Here, the concentration of AgNO3
was high enough (0.25 M), and the molar ratio between the
repeating unit of PVP and AgNO3 was kept at 1.5. Meanwhile,
the presence of PVP and its molar ratio (in terms
of repeating unit) relative to silver nitrate both played key
roles in the determination of the geometric shape and size of
the product. The generated single-crystalline Ag nanocubes
were characterized by a slightly trunctated shape bounded by
{100}, {110}, and {111} facets. Other techniques, including
pulsed laser irradiation [21, 267],  irradiation [68], pulsed
sonoelectrochemistry [58, 268], and ultraviolet irradiation
[117], have proven to be efficient methods to control the
shapes of Ag nanoparticles.

 

[Rick A]

blah-blah-blah......

 

[Mustafa Umut Sarac]

...

 

[lxdude]

blah-blah-blah......

I find it quite interesting.

 

[Mustafa Umut Sarac]

I have a full basic and effective recipe to prepare collodial gold and silver but I forgot which books binder I wrote to I will find in few days and anyone would be able to prepare them. For Gum, Dye Transfer, Autochrome, Inkjet or others , anyone could be able to manipulate the variables first on small batches and than more.

Umut

 

[Mustafa Umut Sarac]

There is an color changing ink on new american banknote , this is an ink which contains collodial gold or silver. There is an extensive list of patents at google patents and uspto.gov.

Particles goes to 100 to 1 nanometer diameter or so , they tend to change their colors with receiving photon, wait, resonate and release an new color. This new color is different than what we see than bigger particles .

Gold tend to go in fuschia color and can be manipulated to wide range of colors including deep reds to purples and green.
Silver goes to yellow and orange colors,green , blue..
Platin goes to brown when it is in nanoparticle state.
Turkovich method is the best to manufacture them. But it needs several heating and cooling steps plus rules while adding new chemicals to solution plus stirring rules.
I will find the recipe of these today. You can google collodial gold silver ink and recieve many patents.

 

[Mustafa Umut Sarac]

Medieval Stained Glass and Nanoparticle Colors

 

[Vaughn]

I used some Colloidal Silver for a persistent infection of the outer ear -- it worked immediately.

 

[Mustafa Umut Sarac]

From Arthur Nash Notebooks of Tiffany Co.

Arthur Nash was a very important glass maker from England and Louis C. Tiffany invited him to US to formulate new glasses and colors at late 19th century. He and his son developed many formulas and pioneered at Glass making and coloring technology. He always kept his secrets in a little notebook and never revealed the formulas to Tiffany.

His notebooks sold to Corning and opened to public.

cobalt oxide blue , uranium oxide yellow , iron oxide green , and he used manganese , arsenic , silver nitrate , potash nitrate , platin , palladium , rb , and many more for their own colors or plasmon colors.

Umut

 

[Randy Moe]

Umut,

Please keep up the good work!

Thank you!

 

[stormpetrel]

Very interesting indeed!

 

[BobCrowley]

Very interesting indeed!

Yes this is. A good compilation Umut. I did some work with photonic crystals tuned to length here http://microphonium.blogspot.com/2011/11/press-release-about-my-work-and-patents.html

One of the intriguing things would be to use these as part of a new color system - perhaps a direct positive color system, that could be electronically activated, instead of with chemicals.

 

[Mustafa Umut Sarac]

Liquid gold compositions
EP 1244753 B1
ÖZET (metnin alındığı doküman: WO2001040392A1)
The present invention relates to a liquid gold composition comprising a gold lustre and an effective amount of an acrylate polymer of the formula (I): -[-CH2-C(R)-]-n, C(O)-O-Y; where R = H or a C1-C4 alkyl group, Y = a C5-C40 hydrocarbyl group, which is monocyclic, bicyclic or tricyclic, which may be further carry ring substituents and n = an integer representing the number of repeat units in the polymer. The gold composition can be used to decorate substrate surfaces and the decoration applied upon firing forms an excellent, bright film of gold on the decorated substrate surface.

HAK TALEPLERI
A liquid gold composition comprising a gold lustre and 0.05 to 50% by weight of an acrylate polymer of the formula:


where
R = H or a C 1-C4 alkyl group,
Y = a C5 - C40 hydrocarbyl group, which is monocyclic, bicyclic or tricyclic, which may be further carry ring substituents, and
n = an integer representing the number of repeat units in the polymer.
A composition according to Claim 1 wherein the gold lustre is a hydrocarbyl mercaptide of gold and is of the formulae:
   Au-S-CH2R1, wherein R1 = alkyl Au-S-CH(R2)R3, wherein each of R 2 and R3 = the same or different alkyl or aryl group (secondary thiols)
Au-S-CR4R5 R6, wherein each of R4, R5 and R6 = the same or different alkyl or aryl group (tertiary thiols)
Au-S-R7 wherein R7 = aryl group or a substituted aryl group (aromatic thiols).
AuSCHRCO2R where R= H, alkyl or aryl and R'=H, alkyl or aryl

A composition according to Claim 2 wherein the hydrocarbyl group in the gold mercaptides are selected from alkyl, cycloalkyl, aryl and aralkyl groups, and the halo-, amino-, and carboxylic acid- substituted derivatives thereof.

A composition according to Claim 2 or 3 wherein the hydrocarbyl groups in the mercaptide is selected from methyl, ethyl, isopropyl, butyl, sec.-butyl, isobutyl, tert-butyl, heptyl, octyl, isooctyl, 2-ethyl hexyl, di-isobutylmethyl, nonyl, tert-nonyl, decyl, tert-decyl, undecyl, tert-undecyl, dodecyl, tert-dodecyl, tridecyl and octadecyl, cyclobutyl, cyclopentyl, cyclohexyl, dicyclohexylmethyl, phenyl, naphthyl, phenanthryl, benzyl, methylphenyl, 2-phenyl ethyl, 4-phenyl butyl, p-tert.-butylphenyl, o-methyl-p-tert.-butylphenyl, pinanyl, mixed methylphenyl, mixed dimethylphenyl, mixed dibenzylmethyl, p-chlorophenyl, pentachlorophenyl, o-carboxy-phenyl and o-aminophenyl groups.

A composition according to Claim 1 wherein the gold lustre is a gold sulpho-resinate.

A composition according to Claim 1 or 5 wherein the gold lustre is a gold sulpho-resinate obtained from a gold (III) salt and a sulphurised terpene, the terpene component of which may be naturally occuring

A composition according to any one of the preceding Claims wherein the cyclic hydrocarbyl group Y is a terpenyl group.

A composition according to any one of the preceding Claims wherein the terpenyl group is derivable from a terpene which is a natural, non-aromatic constituent of an essential oil, containing carbon, hydrogen and optionally oxygen, and/or a synthetic compound which is very closely related to the natural terpenes.

A composition according to Claim 7 wherein the terpenyl group is derived from a terpene is selected from monoterpenes (10 carbons - two isoprene units), sesquiterpenes (15 carbons), diterpenes (20 carbons), triterpenes (30 carbons) and tetraterpenes (40 carbons).

A composition according to Claim 9 wherein the terpenyl group is derived from a bicyclic monoterpene (10 carbons).

A composition according to Claim 10 wherein the terpenyl group is a bicyclic monoterpenyl group selected from bornyl, isobornyl, thujyl, fenchyl, pinocamphyl and isopinocamphyl groups.

A composition according to any one of the preceding Claims wherein the polymers of formula (I) have an average molecular weight in the range from 2,000 to 600,000.

A composition according to any one of the preceding Claims wherein the polymer of formula (I) is poly(isobornyl methacrylate).

A composition according to Claim 13 wherein the polymer has an average molecular weight in the range from 500,000-600,000.

A composition according to claim 13 wherein the polymer has an average molecular weight of approximately 100,000.

A composition according to any one of the preceding Claims wherein said composition contains in addition a solvent capable of forming a substantially homogeneous mixture with the gold lustre and the polymer so as to form a liquid or a smooth paste.

A composition according to Claim 16 wherein the solvent is selected from ketones, aliphatic hydrocarbons, aromatic hydrocarbons, alkyl acetates, glycol ethers, terpenes, natural oils and waxes.

A composition according to any one of the preceding Claims wherein said composition contains in addition a gold flux.

A composition according to Claim 18 wherein the gold flux is selected from salts or resinates of antimony, bismuth, boron, cadmium, cerium, chromium, cobalt, copper, iridium, lead, rhodium, silicon, silver, tin, titanium, vanadium and zirconium.

A composition according to Claim 18 or 19 wherein the amount of flux added to the compositions is in the range from about 0.01 to 10 % by weight of the total composition.

A method of decorating a substrate surface said method comprising applying a composition comprising a gold lustre and 0.05 to 50 % by weight of an acrylate polymer of the formula:


where
R = H or a C 1-C4 alkyl group,
Y = a C5 - C40 hydrocarbyl group, which is monocyclic, bicyclic or tricyclic, which may be further carry ring substituents, and
n = an integer representing the number of repeat units in the polymer in a solvent, and heat-treating the resultant decorated substrate to cure the decoration on the substrate surface.
A method according to Claim 21 wherein the composition is applied on the substrate surface by one or more methods selected from brush coating, spraying, stippling, stenciling, decalomania, direct and offset printing, indirect screen-printing, direct hot- or cold-printing and ink-jet printing techniques.

A method according to Claim 21 or 22 wherein the substrate on which the composition is applied is selected from the group consisting of glass, earthenware, bone china, porcelain, silicate materials, metals, quartz, carbon, mica, plastics, laminates, wood, paper, textiles and leather.

A method according to any one of the preceding Claims 21-23 wherein the composition applied to the substrate surface is as claimed in any one of the preceding Claims 2-20.

 

[Mustafa Umut Sarac]

AÇIKLAMA
[0001] The present invention relates to new and improved liquid gold compositions, a method of preparation therefor and use thereof for decorating substrates.
[0002] Liquid gold compositions have been known in the art and used for gilding and decorating substrates for a long time. Traditional liquid gold compositions contain gold sulpho-resinates in combination with natural resinous materials (by Boudnikoff, Compt. Rend., 196, 1898 (1933) and by Chemnitius, J. Prakt. Chem., 117, 245 (1927)). The gold sulpho-resinates are prepared by the reaction of a gold chloride solution with a sulphurised terpene. These are then diluted with natural oils such as lavender, rosemary and pine oils. Rosin and asphalt resins are added to thicken the compositions so that they are suitable for decorating, gilding or printing applications. Furthermore, small amounts of salts or resinates of metals such as rhodium, bismuth, chromium etc are also added as fluxes to these compositions to improve the lustre of the gold in the fired product and also to improve the adhesion of the gold applied to the substrate upon firing. In preparing other compositions, various gold mercaptides have been used. For instance, US-A-2490399 describes the use of gold mercaptides of cyclic terpenes but does not provide any structure for the resultant mercaptide. Again, the mercaptide of gold prepared from thio-borneol has been described in the Journal of the Society of the Chemical Industry, Japan, 38, Supplement 617B (1935) by Nakatsuchi although this reference makes no mention of the possibility of using such compounds in decorating or gilding compositions. According to US-A-3163665, the gold thiolates derived from cyclic terpenes have the disadvantage of requiring relatively high firing temperatures, thereby limiting their use on substrates such as glass, ceramics etc. and consequently recommends the use of non-terpenoid gold secondary mercaptides. Similarly, US-A-3245809 claims and describes the use of a liquid gold decorating composition comprising a nuclear-substituted gold aryl mercaptide wherein the sulphur is attached directly to the aryl nucleus which is already substituted by an alkyl group in solution in an organic vehicle and a gold flux. The specific aryl mercaptides disclosed include gold p-tert.-butylphenyl mercaptide prepared from p-tert.-butylbenzenethiol and aurous chloride. The fluxes used are said to contain small amounts of salts or resinates of rhodium or iridium to improve the continuity and brilliance of the gold film and the only other component, apart from the vehicle (solvent), is rosin dissolved in oil of turpentine. No synthetic polymeric thickeners are mentioned in these compositions.
[0003] More recently, US-A-5328769 states that the conventional isooctyl- and tert.-dodecyl-gold thioglycolates are not satisfactory for use in gilding preparations for decorating ceramics because the drying time for such preparations is very long. This document also states that gold (I) bornyl mercaptide (described in US-A-4221826) proved advantageous in the production of integrated electronic circuits but that such compounds "have the disadvantage of a partially very unpleasant odour which becomes particularly noticeable in a disturbing manner when the gold preparations are applied by heat". Thus, instead, this reference claims and describes a method of gilding solid bases, by applying a gold preparation comprising a gold mercaptocarboxylic acid ester on to a solid base followed by firing. The "gold preparation" also contains fluxing agents including in particular, sulphoresinates, resinates, naphthenates, carboxylates, and dithiocarbamates of the elements B, Si, V, Cr, In, Sn, Pb, Bi and Rh. These compositions are also stated to contain one or several resins from the series of wood resins and synthetic resins (e.g., hydrocarbon resins, polyacrylates and polymethacrylates). However, no preparations containing these synthetic resins are described and no particular benefit or advantage is said to accrue by the use of such synthetic resins.
[0004] Thus, the liquid gold compositions typically involve the use of either (i) a gold mercaptide compound, or, (ii) a gold sulpho-resinate, in combination with natural resins (e.g. rosin or colophony, often in their sulphided form, or, asphalt) and some synthetic resins such as e.g. phenol-aldehyde resins. The gold sulpho-resinates of the present invention in turn can be obtained from a gold (III) compound or gold (I) salts or compounds and a sulphurised terpene, the terpene component of which may be naturally occuring. These compositions may have overcome some of the traditional problems such as e.g. adhesion, drying, odour etc. However, they still have one or more of the following disadvantages:
[0005] Unsatisfactory application of ink onto substrate; undesirable changes in viscosity during application; formation of defective films on application to the substrate prior to firing; dewetting of ink on substrate (often caused by sensitivity of ink to dust particles) leading to pinholing; formation of defective films having 'black spots' on firing which cannot be envisioned prior to firing; poor adhesion of the gold film on to the substrate; and observation of poor colour, usually red, on the reverse of transparent substrates such as e.g. glass.
[0006] It has now been found that the performance of the liquid gold compositions in all the above aspects can be substantially improved by choice of a specific synthetic polymer for thickening such compositions.
[0007] Accordingly, the present invention is a liquid gold composition comprising a gold lustre and an effective amount of an acrylate polymer of the formula:

where
R = H or a C1-C4 alkyl group,
Y = a C5 - C40 hydrocarbyl group, which is monocyclic, bicyclic or tricyclic, which may be further carry ring substituents. and
n = an integer representing the number of repeat units in the polymer.
[0008] By the expression "gold lustre" as used herein and throughout the specification is meant a derivative of gold which may be a sulpho-resinate, hydrocarbyl (such as e.g. alkyl or aryl) mercaptide, or a mercaptocarboxylic acid or an ester thereof. The term gold sulpho-resinate in the context of the present invention means a gold compound formed from a gold (III) compound or a gold (I) compound and sulphurised resin group. As mentioned previously, the gold sulpho-resinates can be obtained from a gold (III) salt and a sulphurised terpene, the terpene component of which may be naturally occuring. Specific examples of such mercaptide compounds include:
a. hydrocarbyl gold mercaptides of the formulae Au-S-CH2R1, wherein R1 = alkyl
Au-S-CH(R2)R3, wherein each of R 2 and R3 = the same or different alkyl or aryl group (secondary thiols)
Au-S-CR4R5 R6, wherein each of R4, R5 and R 6 = the same or different alkyl or aryl group (tertiary thiols)
Au-S-R7 wherein R7 = aryl group or a substituted aryl group (aromatic thiols).
Au-SCHR-C02R' where R = H, alkyl, aryl and R' =H, alkyl, aryl
[0009] More specifically, references to the hydrocarbyl groups, such as e.g. alkyl or aryl groups, in the formulae above includes within its scope the respective groups selected from alkyl, cycloalkyl, aryl and aralkyl groups, and any substituted derivatives thereof. For example the substitued derivitives may be halo, amino, carboxylic acid or ester groups. Specifically, the hydrocarbyl groups in the mercaptide may be any one of methyl, ethyl, isopropyl, butyl, sec.-butyl, isobutyl, tert-butyl, heptyl. octyl, isooctyl, 2-ethyl hexyl, di-isobutylmethyl, nonyl, tert-nonyl, decyl, tert-decyl, undecyl, tert-undecyl, dodecyl, tert-dodecyl, tridecyl and octadecyl, cyclobutyl, cyclopentyl, cyclohexyl, dicyclohexylmethyl, phenyl, naphthyl, phenanthryl, benzyl, methylphenyl, 2-phenyl ethyl, 4-phenyl butyl, p-tert.-butylphenyl, o-methyl-p-tert.-butylphenyl, pinanyl, mixed methylphenyl, mixed dimethylphenyl, mixed dibenzylmethyl, p-chlorophenyl, pentachlorophenyl, o-carboxy-phenyl and o-aminophenyl groups. These mercaptides can be prepared by admixing the appropriate hydrocarbyl mercaptan with a gold salt suitably a halogenated auric salt such as auric bromide. auric chloride. auric iodide, potassium bromoaurate or potassium iodoaurate as described in US-A-3245809.
[0010] The acrylate polymers present in the compositions of the present invention are of the formula:

where
R = H or a C1-C4 alkyl group,
Y = a C5 - C40 hydrocarbyl group, which is monocyclic, bicyclic or tricyclic and which may be further carry ring substituents, and
n = an integer representing the number of repeat units in the polymer.
[0011] Cyclic hydrocarbyl groups representing Y are suitably terpenyl groups derivable from a terpene and the term "terpene" as used herein and throughout the specification is meant to describe a cyclic compound which is a natural, non-aromatic constituent of an essential oil, containing carbon, hydrogen and optionally oxygen, and/or synthetic compounds which are very closely related to these natural terpenes. These terpenes can be selected from the following classes based on the number of isoprene units within the structure: monoterpenes (10 carbons - two isoprene units), sesquiterpenes (15 carbons), diterpenes (20 carbons), triterpenes (30 carbons) and tetraterpenes (40 carbons). Of these. the group Y is preferably a terpenyl group derived from a bicyclic monoterpene (10 carbons). More specifically, examples of bicyclic monoterpenyl groups include bornyl, isobornyl, thujyl, fenchyl, pinocamphyl and isopinocamphyl groups.
[0012] Such polymers can be prepared by solution or suspension polymerisation reaction of the desired monomer and a suitable initiator under dry anaerobic reaction conditions. The polymers of formula (I) suitably have an average molecular weight in the range from 2.000 to 600,000, preferably from 30,000 to 600,000, more preferably from 50,000 to 200,000.
[0013] An example of a polymer of formula (I) is poly(isobornyl methacrylate) which in turn can be made from the corresponding isobornyl methacrylate monomer and having an average molecular weight in the range from 500,000-600,000. Such polymers are commercially available (ex Aldrich Chemicals).
[0014] The amount of the polymer (I) in the compositions of the present invention is suitably in the range from 0.05 to 50% by weight, preferably from 0.5 to 30% by weight, typically 1 to 10% by weight of the total composition. The amount of the polymer (I) used may vary within these ranges depending upon the molecular weight thereof and the method used for the application of the liquid gold composition on the substrate.
[0015] The compositions of the present invention suitably contain in addition a solvent to provide a vehicle for applying the gold composition onto a substrate. The solvent should be such that it is capable of forming a substantially homogeneous mixture with the gold lustre and the polymer so as to form a liquid or a smooth paste. Thus, the solvent chosen should be such that it is commensurate with the desired physical properties in the composition such as e.g. oilness, viscosity, evaporation rate, surface tension and tack, depending upon the manner in which the composition is to be applied to the substrate surface. Suitable examples of such solvents include ketones, aliphatic hydrocarbons, aromatic hydrocarbons. alkyl acetates, glycol ethers, terpenes, natural oils and waxes. More specifically, these may be one or more of the following: methyl ethyl ketone, cyclohexanone, ethyl acetate, ethyl lactate, butyl lactate, amyl acetate, cellosolve, butanol, cyclohexanol, propylene glycol butyl ether, propylene glycol phenyl ether, dipropylene glycol dimethyl ether, propylene glycol methyl ether acetate, toluene, xylene. petroleum ether, terpenes such as pinene, dipentene, dipentene oxide, natural oils such as lavender, rosemary, aniseed, sassafras, wintergreen, fennel, and turpentine. Various other subsidiary resins such as rosin, asphalt, colophony, poly(terpene), phenolformaldehyde resins and the like may also be present in the compositions of the present invention.
[0016] The compositions of the present invention may contain in addition gold fluxes which are small amounts of metal salts or resinates and these determine the behaviour of the gold film during application on the substrate and subsequent firing thereof at elevated temperature. The specific choice of flux will be determined not only by the aforementioned conditions but also by the substrate upon which the composition is to be applied, the method of application as well as the need to provide lustre to the metal film applied on the substrate. Examples of fluxes that may be used include salts or resinates of antimony, bismuth, boron, cadmium, cerium, chromium, cobalt, copper, iridium, lead, rhodium, silicon, silver, tin, titanium, vanadium and zirconium. The fluxes also improve the adhesion of the gold metal film on the substrate and provide resistance to abrasion. The fluxes achieve these functions by initially melting and then forming a thin, protective, transparent film on the metal film during the firing process. Of these, fluxes containing salts or resinates of rhodium and/or iridium are most preferred.
[0017] The amount of flux added to the compositions of the present invention is suitably in the range from about 0.01 to 10 % by weight, preferably from about 0.05 to 5.0 % by weight of the total composition.
[0018] The substrate surface on which the compositions of the present invention are applied may be suitably of relatively refractory materials and are preferably selected from the group consisting of glass, earthenware, bone china, porcelain, silicate materials, metals, quartz, carbon, mica and the like.
[0019] The compositions of the present invention may be applied on the substrates by any of the known application methods. For instance, they may be applied by simple brush coating, spraying, stippling, stenciling, decalomania, direct and offset printing, indirect screen-printing, direct hot- or cold-printing or ink-jet printing techniques.
[0020] Thus, according to a further embodiment the present invention is a method of decorating substrate surfaces, said method comprising applying a composition comprising a gold lustre and the polymer (I) in a solvent, and heat-treating the resultant substrate to cure the decoration on the substrate surface.
[0021] As indicated above, once the composition of the present invention in a solvent is applied as a decoration on a substrate surface, the decoration is suitably cured by heat-treating the decorated substrate at elevated temperature. The heat-treatment temperatures used will depend upon the nature of the gold lustre used, the solvent used and the amount of the polymer (I) used, although more importantly, it will depend upon the substrate surface upon which the decoration is applied. Thus, for refractory substrates, heat-treatment/firing temperatures may vary over a wide range from about 300-1300C, preferably from about 500-900C, typically from about 550-900C. Temperatures towards the upper end of the ranges specified above e.g. around 900C may be required for substrates such as porcelain.
[0022] A feature of the compositions of the present invention is that the use of the specific polymers (I) showed excellent compatibility with the gold lustres used. Moreover, on firing, the major problem of 'black spot' formation with conventional compositions was no longer observed. Also, on glass, reverse colour is improved over that of currently available compositions for this purpose. Analogous formulations prepared using commercially available polymers corresponding to polymer (I) but in, which the terpenyl group Y is replaced by a relatively simple alkyl group, such as eg methyl, ethyl or butyl groups, did not show similar improvement in the decorative films formed.
[0023] The compositions and process of the present invention are further illustrated with reference to the following Examples:
EXAMPLES:
Bright gold preparations
[0024] All composition data is in % by weight and all firing temperatures are in C. The gold sulpho-resinates used are available from Johnson Matthey PLC and the silver sulpho-resinates were prepared from silver and sulphurised balsam. A solution of poly(isobomyl methacrylate) was prepared in the stated solvent at various concentrations as specified in each Example below. All formulations were prepared to give 'a concentration of 10% wt Au. This was then used to prepare the following liquid gold formulations. All formulations were prepared to give a concentration of 10wt%Au.
EXAMPLE 1
[0025]
18.3 Au(SC6H4-p-CMe3) (prepared according to the method described in US-A-3,245,809)
40 Poly(isobornyl methacrylate) (ex Aldrich. MW 550.000) as a 30% by weight solution in cyclohexanone
4 Rh-ethyl-hexanoate dissolved in cyclohexanone (0.12% Rh)
37.7 Xylene
100
Comparative Test
(not according to the invention):
[0026]
18.3 Au(SC6H4-p-CMe3) (prepared according to the method described in Example 1(F) of US-A-3,245,809)
40 Poly(butyl methacrylate) (NeocrylB804, ex Zeneca Resins) as a 30% by weight solution in cyclohexanone
4 Rh-ethyl-hexanoate dissolved in cyclohexanone (0.12% Rh)
37.7 Xylene
100
[0027] Each of the above two formulations were gilded onto ceramic ware, and fired at 865C over a 1 hour cycle. The formulation of Example 1 gave bright golden films free of film defects whereas the formulation of the Comparative Test gave poor quality films.
EXAMPLE 2
[0028]
30.86 Gold sulpho-resinate
40 Poly(isobornyl methacrylate) (ex Aldrich Chemicals) as a 20% by weight solution in cyclohexanone
4 Rh-ethyl-hexanoate dissolved in cyclohexanone to a final concentration of 3% Rh
0.54 Cr Nuosyn5 to a final concentration of 7.45% Cr2O3
3.67 Bismuth octoate lustre to a concentration of 10% Bi2O3
20.93 Rosemary oil
100
[0029] The formulation was applied to china and porcelain by brush over a large area. Upon firing, it gave a bright gold film of similar colour to commercial golds with no film defects (ie black spots) observed in the film.
EXAMPLE 3
[0030] The process of Example 2 was repeated except that sulphided colophony resin was used instead of the poly(isobomyl methacrylate). Bright films, with film defects were obtained upon application and subsequent firing.
EXAMPLE 4
[0031]
18.3 Au(SC6H4-p-CMe3)
29.9 -pinene
21.2 Silver sulpho-resinate solution (2% wt Ag) in form
2.4 Anethol
1.2 Rosemary oil
10 Dipentene
10 Poly(isobornyl methacrylate) as a 20% wt cyclohexanone solution
6 Poly(isobomyl methacrylate) as a 20% wt solution in lavender oil
1 Rh-ethyl-hexanoate dissolved in cyclohexanone (0.12% Rh)
[0032] The formulation was applied onto a Koelner Stange glass at 580C and upon firing bright films free of film defects were obtained.
EXAMPLE 5
[0033]
18.3 AuSC6H4-p-CMe3
40 30% wt Poly(isobornyl methacrylate) (100,000 mwt supplied by Scientific Polymer Products Inc.) solution in cyclohexanone
4 Rh-hexanoate dissolved in cyclohexanone (0.12%Rh)
37.7 Xylene
[0034] The formulation above was gilded onto ceramic ware , fired at 840°C over 1hr. Bright gold films free of defects were produced.

 

[Mustafa Umut Sarac]

Above patent is indirectly related with Zsolnay luster ware secret and given to me when I was researching it.