KR100227027B1 - Precious metal composition - Google Patents

Abstract

For example, a homogeneous composition for burning and forming a precious metal film of at least one of platinum, palladium, gold or silver on a substrate to decorate a tableware consists of a polymer resin and a water and a precious metal thiolate solution in a co-solvent, It contains 3-22% by weight of noble metal as thiolate and as the composition on the substrate dries, burns and is continuously heated, the water is evaporated, leaving a homogeneous composition of resin and thiolate in the co-solvent and then co-solvent The evaporation consists of co-solvent, resin and thiolate, in which thiolate is broken down into noble metals while thiolate leaves a homogeneous composition in the resin and then the resin is volatilized.

Description

[Name of invention]

Precious metal composition

Detailed description of the invention

The present invention relates to a composition for burning a composition to form a noble metal film and a method of forming a noble metal film on a substrate using the composition.

Compositions that burn to form noble metal (meaning at least one of platinum, palladium, gold and silver) coatings are particularly useful for decorating ceramic or glass substrates.

Commercially available solutions for this purpose include (a) noble metal compounds, which are organic solvents as the main raw materials, and burn to decompose to form precious metals, and (b) rhodium, bismuth or chromium to improve the color, adhesion or gloss of the burned coating. It is a complex mixture containing a metal compound such as, and (c) (a) and (b) to dissolve or contain a resin and an organic solvent.

For example, in preparing, transferring, or using a composition containing an organic solvent, reducing or eliminating such organic solvents in order to reduce or eliminate any environmental risks that the organic solvent presents from the gases released when the composition is applied or combusted. desirable. This task, however, is not straightforward because the composition still needs to be stable and is easily applied and produces an excellent coating upon combustion. Water based compositions rather than organic solvents have the added advantage of being able to wash materials such as brushes or screen printing screens or stencils with which the composition comes into contact with an aqueous cleaner. Despite these advantages, to our knowledge, there are no commercially available waterborne polished gold compositions. Aqueous compositions are now invented.

British Patent Specification No. 2097811A discloses a paint for painting pottery, which is polyvinylpyrrolidone or a mixture of polyvinylpyrrolidone and aqueous polyethylene oxide: 15-40% by weight, ethylene glycol and / or cropropylene Glycol and optional water: 45 to 85% by weight.

According to the above specification, the coloring material is an oxide and a safe organogold compound.

British Patent No. 2216536A discloses an aqueous acrylic resin dispersion 3 comprising 10-40% by weight of powdered gold and / or poorly soluble gold compounds, 2-20% by weight of polyvinylpyrrolidone, and 30-60% by weight of solids. Burnish gold compositions are disclosed which contain -30% by weight and 5-50% by weight of water.

The present invention provides a homogeneous composition for forming a noble metal coating of at least one of platinum, palladium, gold and silver on a substrate by combustion, the composition comprising a polymer resin and a noble metal in water and co-solvents. Consisting of a solution of thiolate, the composition containing 3-22% by weight of a precious metal as thiolate, and as the composition on the substrate is dried, continuously heated and burned, the water evaporates to form a resin and thiolate in the co-solvent It consists of a co-solvent, a resin and a thiolate, which leaves a homogeneous composition of and then the co-solvent evaporates to leave a homogeneous composition of thiolate in the resin and then the thiolate decomposes into a noble metal while the resin is volatilized. .

The present invention also provides a method of forming a noble metal film on a substrate, which comprises applying a composition on a substrate and drying and burning the applied composition.

The present invention also provides a transfer body for supporting a composition that is dried on the composition.

Some of the thiolates of the present invention are novel compounds and the present invention provides novel compounds such as the characteristic thioleates which are gold compounds of the general formula AuSR "or salts thereof, wherein R" is a 4,6-di Hydroxy-2-mercaptopyrimidine, or an alkyl group thereof, to represent N- (mercaptoalkanoyl) glycine containing 1 or 2 carbon atoms.

The present invention also provides a novel thiolate comprising reacting a compound of general formula AuCl (SR ′ ₂ ) with a thiol of general formula HSR ″ in a solvent to form a gold compound and forming a sulfide of formula SR ′ _{2 in} a solvent. It provides a manufacturing method.

The present invention also provides a novel thiolate production method consisting of reacting tetrahalorate with a thiol of actual HSR ″ to form a gold compound.

The invention also relates to thiols of the formula HSR " There is provided a novel method for preparing thiolates consisting of reacting a gold (I) amine complex of where Hal represents a halogen atom and each R "is the same or different and represents an aliphatic, aromatic or heterocyclyl group or 2 Denotes a cyclic amine for forming a gold compound together with the N element.

Although the composition still contains a co-solvent, the composition is water based. It can be diluted with water (i.e. water-dilute) and does not contain as many organic solvents as in conventional liquid noble metal chemicals. It is easily applied and produces an excellent coating by combustion.

It is surprising that water soluble (not colloidal) precious metal compounds can be employed. The present invention relates to a composition in which the noble metal compound is homogeneous, preferably in solution, if the compound is dissolved thiolate until the noble metal compound decomposes into the noble metal at the same time its carrier matrix is volatilized, as the compound is gradually heated by combustion. Based on the development that it can remain.

Clearly the invention is described as heating to leave a homogeneous composition of a noble metal thiolate in a co-solvent, preferably a solution and then to leave a homogeneous composition of a thiolate in a resin, preferably a solution. However, it should be noted that thiolates may undergo structural changes during heating, and it is important that the subsequent precious metal compounds remain in a homogeneous composition, preferably in solution, in some form. Likewise, the resin is broken off while it is volatilized.

As the composition is heated, the homogeneous composition remains so that the thiolate does not precipitate until it decomposes into a noble metal while the resin is volatilized. The thiolate is in the solution of the initial composition and preferably remains in solution during heating until the resin decomposes into noble metals during volatilization. Thus, the composition comprises water and a solution of a thioleate of a noble metal with a polymeric resin in a co-solvent, wherein the composition contains 3-22% by weight of the noble metal as a thiolate, and on the co-solvent, resin and thiolate substrate As the composition dries, continues to be heated and burns, it is preferred that the water evaporate leaving a solution of the resin and thiolate in the co-solvent and then the thiolate decomposes into the precious metal while the resin is volatilized.

The composition typically contains 5-85% by weight of water. Where percentage is by weight. The composition may be diluted with water for application. The composition preferably contains 15-70% by weight, in particular 40-55% by weight of water. It is particularly advantageous for the composition to contain a greater amount of water than the total amount of all organic solvents.

Precious metals typically consist of gold or platinum, in particular gold.

Specific examples are:

(a) gold

(b) platinum

(c) gold and platinum

(d) gold and palladium

(e) gold, platinum and palladium; And

(f) is any one of (a)-(e) and

Preferably the noble metal is (a), (b), (d) or any one of them and silver.

Thiols are analogs of alcohols, that is, organic compounds in which oxygen atoms in the hydroxy groups of alcohols are generally substituted with sulfur atoms. Metal thiolates are analogs of thiols in which the hydrogen atom of the SH group is generally substituted with a metal atom. The precious metal thioleate must form a water / co-solvent mixture solution and must be capable of meeting other required functions. Generally adopted thioleate has a solubility of at least 100, preferably 200-300 g / l, in water at 20 ° C. Preferably the thiolate, usually in salt form, is also soluble in water only. Advantageously noble metals, especially gold thiolates, begin to decompose into noble metals above 200 ° C. and these thiolates tend to give a bright coating rather than a dull coating after combustion. Suitable thiolates are known to be compounds.

The thiolate may be aliphatic, aromatic or heterocyclic thiolate and is preferably of the formula -COOH, -SO ₂ OH, -OH, -CO.NH ₂ , -NH in which the nitro group and its H element are optionally substituted At least one group selected from ₂ or -OP (O) (OH) ₂ or salts thereof. Such thiolates are described below in connection with gold, which is a precious metal. Thus, preferred groups in thiolates are of the formula:

Au-S-R-H or Au-S-R-X

Or two salts wherein X is a formula -COOH, -SO ₂ OH, -OH, -CO.NH ₂ , -NH ₂ or -OP (O) (OH) ₂ , wherein its hydrogen atom is optionally substituted Represents one group or nitro group, and R represents a divalent organic group.

Although the gold compound is described as a mononuclear structural formula such as Au-S-R-X in the conventional manner, it will be appreciated that in fact they may be multinuclear structural formulas satisfying the bivalent properties of the gold (I) complex.

Any substituent in X is generally an optionally substituted amino group, such as an aliphatic, aromatic or heterocyclic group or an amino group mono- or disubstituted with, for example, alkyl of 1-6 carbon atoms. Aliphatic groups are usually alkyl of 1-6 carbon atoms, such as ethyl, isopropyl, or n-butyl. Aromatic groups are usually optionally substituted phenyl, and substituents are usually mercaptos wherein the alkyl or hydrogen atom of the X 1-6 carbon atom is optionally substituted with a gold atom as defined herein. Heterocyclic groups are usually optionally substituted purine, pyridine or pyridine and the substituents are usually X, alkyl of 1-6 carbon atoms as defined herein or an aromatic group as described above. The -CO.NH ₂ , or -NH ₂ group can be mono- or double-substituted, for example, with alkyl of 1-6 carbon atoms optionally substituted with X as defined herein. In case R represents a divalent aliphatic group (ie the group attached to S is aliphatic rather than aromatic or heterocyclic), it is generally defined by X, generally by one X, as defined above Or a divalent hydrocarbon of 1-7 carbon atoms (eg, alkane or toluene of 1-6 carbon atoms) optionally substituted with an oxo group on a non-terminal carbon atom. If R represents a divalent aromatic group (ie the group attached to S is aromatic rather than aliphatic or heterocyclic), it is generally substituted optionally with X or generally with 1 X as defined above Divalent benzene. In case R represents a divalent heterocyclic group (ie the group attached to S is heterocyclic rather than aliphatic or aromatic), it is generally referred to as X (generally as one X) as defined above. And / or divalent pyrimidine, purine or pyridine optionally substituted with phenyl (generally no more than 1 phenyl) and / or alkyl of 1-6 carbon atoms (generally no more than one alkyl group).

X preferably represents -COOH.

In certain embodiments, -RX is -CH ₂ CH ₂ X,

Where X represents -COOH, -C ₆ H ₄ represents divalent benzene and C ₃ H ₃ N ₂ represents imidazol-4-yl.

In another specific embodiment, -RX represents -CH ₂ CH ₂ X or -CH ₂ C ₆ H ₄ -pX wherein X is a nitro group or a group of formula -SO ₂ OH, -OH or -NH ₂ And C ₆ H ₄ represents divalent benzene.

In another specific embodiment, -RX represents -C ₆ H ₄ -pX wherein X represents a nitro group or a group of formula -SO ₂ OH, OH or -NH ₂ and CH ₆ H ₄ represents divalent benzene Indicates.

In another specific embodiment of the gold compound having the general formula Au-S-R-H or Au-S-R-X, H-S-R-H or H-S-R-X is represented by;

4,5-diamino-6-mercapto-2-phenylpyrimidine,

2-amino-6-mercapto-8-methylpurine,

2-mercapto-4-amino-pyridopyrimidine,

2- mercaptopyridine,

2- mercaptobenzoxazole,

2-mercaptobenzimidazole,

5-mercapto-1-methyltetrazole,

4-mercaptopyridine,

2-mercapto-5-nitrobenzimidazole or

4-amino-6-hydroxy-2-mercaptopyrimidine

Indicates.

In preferred gold compounds, the sulfur atom bonded to the gold atom is bonded to a carbon atom having a substituted amido group or separated by one carbon atom from the carbon atom.

It includes.

Specific examples of this class are gold compounds of the general formula Au-S-R-H or Au-S-R-X, wherein H-S-R-H or H-S-R-X is:

N- (2-mercaptopropionyl) glycine,

N- (3-mercaptopropionyl) glycine,

N- (2-mercaptoacetyl) glycine,

2-mercaptoacetyl-L-histidine or

2-mercaptopionyl-L-histidine

Those are the things that represent.

Other preferred gold compounds are

Wherein n is a natural number of 0 or 1 or more, and Y represents an alkanoyl group which is a hydrogen atom or a 2-6 carbon atom which may optionally have a single amino (carboxyl) methyl group. The amino (carboxyl) methyl group, if present, is generally present at the terminal carbon of the alkanoyl group.

In general, n represents 0 or a natural number of 1 to 4.

Particular examples of this class are gold compounds of the general formula Au-S-R-H or Au-S-R-X, in which H-S-R-H or H-S-R-X

Acetylcysteine,

Glutathione or

Such as those representing L-cysteine.

Certain preferred acid gold thiolates have the general formula:

Phosphorus N- (2-mercaptopropionyl) glycine gold (I), which is believed to be multinuclear as discussed above, but alternatively it may be represented in the form of zwitter ions as follows:

Reference is made to British Patent Specification No. 2047672A regarding gold thioleate. This reference relates to the preparation of a ^195m Au-containing solution by adsorbing ^195m Hg with a specific adsorbent and then eluting ^195m Au with both radioisotopes with a specific adsorbent, irrespective of film formation. Table 1 on page 5 of the document combines an adsorbent and an eluent, and among these adsorbents is an aqueous mercaptopropionylglycine solution. There are no special inclusions regarding the use of these eluents and no specific data regarding current gold thiolates. Example II describes a series of experiments in which a specific liquid containing ¹⁹⁸ Au is passed through a specific adsorbent. The above example specifically illustrates that the isotope ^198m Au can be adopted in place of both radioisotopes ^195m Au because of the half-life of ^195m Au. The examples describe the preparation of a solution by dissolving 1-3 μg of gold containing ¹⁹⁸ Au in 1 mL of an aqueous solution containing a pH of about 5-6 and one of the so-called gold ion mixtures containing 0.001-0.1 mol. It is. It is noted in the table that mercaptopropionyl glycine is one of the catalysts and employing the adsorbent SiO ₂ / Ag leaves 88% of ¹⁹⁸ Au without adsorption.

Adopting mercaptopropionyl glycine as a catalyst does not provide the current gold thioleate, but instead provides gold with a portion adsorbed strongly on the surface of the metal, like N- (2 mercapto-propionyl ) Does not have one gold atom per glycine ligand. In any case, the gold material proposed or disclosed in the above references is radioactive. They collapse and gradually become less radioactive, but some radioactivity remains. Gold in current gold thiolates is preferably natural gold, which is non-radioactive. Therefore, it is preferred that the gold in current N- (2-mercaptopropionyl) glycine gold (I) or salts thereof is non-radioactive (not implying a mixture of non-radioactive and radioactive). It is preferred that not only N- (2-mercaptopropionyl) glycine gold (I) or salts thereof, but the current thiolate as a whole are non-radioactive.

The optionally substituted sulfo groups (-SO ₂ OH) that X can represent in current gold thiolates introduce more sulfur, which forms sulfur oxides when the composition burns to form a coating. It is less desirable to have a value. Nitro and optionally substituted hydroxy groups make water-soluble thiolates less stable to reduction than ideal and X is less preferred to have any of these values. In general, it is most preferred that X represents an optionally substituted carboxy.

Thiolates may be in the form of salts. Salts may be formed with bases, for example because of the carboxy or sulfo groups which X may represent. Thiolates which form salts with bases can be used in the base solution which forms the salt therein. The salt is preferably formed with an organic base which is ammonia or in particular an optionally substituted amine, wherein the substituent is for example alkyl of 1-6 carbons optionally substituted by X as defined above. Particularly substituted substituted amines of interest are triethylamine, ethanolamine, diethanolamine, triethanolamine, pyridine, morpholine or diisopropylamine, in particular the first four of them.

If the current thiolates are new, they can be prepared by known methods. If the thiolate is a salt, it can be prepared, for example, by reaction with a base.

When the current thiolate is of the general formula AuSR "is a gold compound or salt thereof, where R" is H- ", its alkyl group represents N- (mercaptoalkanol) glycine containing 1 or 2 carbon atoms, Mercaptoalkanoyl) glycine is:

N- (2-mercaptoacetyl) glycine,

N- (3-mercaptopropionyl) glycine, or

It can be seen that it is N- (2-mercaptopropionyl) glycine.

The last of the above is particularly excellent.

Current thioleates can be prepared by Inorganic Synthesis, Vol. 23, 191 (1985) by AK R-Saadi et al.

It can be represented by. Au (III) in tetrachloroorate anion form is reduced to Au (I) by a water-soluble sulfide of the general formula SR ′ ₂ . Each R 'group is the same or different, preferably representing methyl, ethyl or 2-hydroxyethyl. Preferably the water soluble sulfide is ethyl or 2-hydroxyethyl sulfide. Thiol HSR "adds a suitable thiol ligand, which is typically a yellow solution in the case of mercaptosuccinic acid at room temperature, but usually as a white precipitate, the gold thiolate is prepared. The reaction solvent is generally water, ethanol or isopropanol Soluble inorganic salts (eg NaCl) are extracted by washing with water, the production rate of gold thioleate is at least 80% (based on gold) and the remaining solution is water. (Eg, an organic base which is an optionally substituted amine) is dissolved in water to form the corresponding salt, in this case a substituted ammonium salt.

The present gold thiolates can be prepared by reacting tetrahalorate (particularly tetrachloroorate or tetrabromoorate) with thiols of the general formula HSR "to form gold compounds.

Thiol as the general formula HSR " By reacting with a phosphorus gold (I) amine complex, where Hal is a halogen atom (preferably chlorine or a cancel atom) and R " is the same or different and represents an aliphatic, aromatic or heterocyclic group or is preferably 2 R ″ 'represents a cyclic amine (benzotriazole or pyridine) for forming a gold compound together with N atoms. Aliphatic, aromatic or heterocyclic groups which R ″ 'may represent may be those groups described above as being substituted by X.

The present thiolate can be formed in situ in the present composition, for example by forming a salt therein as described above.

The composition contains 3-22% of precious metals like thiolate. The composition contains 8-12% of noble metals, especially gold, as thiolates. The composition in particular the gold thiolate contains 10-40% preferably 14-26% thiolate.

The polymer resin must form a homogeneous composition with the other components and can also meet all desired functions. The resin preferably forms a solution of a water / co-solvent mixture, which may be in dispersion or suspended form. Preferably the resin is dissolved in water or forms a clear dispersion. Suitable resins are known materials. Polyacrylic, polymethacrylic, polyvinylpyrrolidone, polycellulose ether, polyamide, polyethylene glycol, polyester, polyacrylamide, polyvinylacetate, polyvinyl alcohol, alkyd, polyamine or polyurethane, resin or theirs Mixtures can be used. The resin may be in the form of a copolymer or a graft polymer. The resin may comprise solubilizing groups, in particular carboxylates and / or hydroxy and / or amino groups, in particular carboxylate groups, in order to improve the water solubility of the resin. Preferably, at least one of polyvinylpyrrolidone resin, polymethacryl resin and polycellulose ether resin, and generally at least one of polymethacryl resin and polycellulose ether resin, for example, is generally composed of one. Resins tend to volatile steadily over a certain temperature range without the volatilization of all materials at the same temperature. Preferably the current resins are selected from those which volatilize in the range of at least most of them being 200-550 ° C. Preferably, the resin is composed of polyvinylpyrrolidone, polymethacryl or polycellulose ether resin, the majority of which is volatilized in the above temperature range.

During combustion, the thiolate forms a uniform composition and preferably forms a solution, and then the resin must meet the current requirements for thiolate to decompose into precious metals during the volatilization of the resin. For example, gold mercaptosuccinic acid, which decomposes into gold at around 150 ° C., is used in a composition similar to the current composition, but its resin begins to evaporate at around 200-300 ° C. and then a homogeneous composition of thiolate in the resin (such as a solution ) Is not formed. Instead, premature dispersions of gold are formed in the resin. Thus, a matte film is formed. However, the same resin can be successfully employed to produce a gloss gold film with a thiolate that meets the above requirements and the same thiolate can be successfully employed to produce a gloss gold film with a resin that meets the above requirements. have. For example, N- (2-mercaptopropionyl) glycine gold (I) starts to decompose around 200 ° C. and decomposes to gold near 280-330 ° C .; It is unsuccessful with gold mercaptosuccinic acid and can be employed to successfully produce glossy gold coatings with resins that volatilize around 280-300 ° C.

The composition may contain up to 5% resin, but generally contains 5-45%, in particular 7-13%. For thiolates, the weight ratio of the resin to precious metals, especially gold, can be at least 1: 1, 1.2: 1 or 1.5: 1, which tends to produce better, no scum and glossy coatings on combustion. . However, satisfactory gloss coatings can be obtained even at a ratio of 0.1: 1 to 1.5: 1. Representative compositions have a ratio of 1: 1.

The co-solvent should dissolve the noble metal thioleate with water to form a homogeneous composition with a resin, preferably a solution, and be capable of meeting other required functions. The cosolvent has, for example, a boiling point between 100 and 220 ° C., preferably between 100 and 280 ° C. Preferred groups of co-solvents are water-miscible alcohols, ethers or esters especially water miscible alcohols. Preferably the co-solvent is 1,2-propanediol, 1,3-propanediol, n-butanol, tetrahydrofuran acetate, glycerol, glycerol diacetate or ethyl lactate, especially 1,2-propanediol, 1, Consisting of 3-propanediol or ethyl lactate. In particular, co-solvents can affect the gloss of the coating during combustion.

The composition generally comprises 5-45% preferably 15-30% such as 25-30% co-solvent.

The specific components and their amounts depend on each other and it is estimated that candidates can be easily measured. For example, when the resin is a cellulose resin, the content of the co-solvent in the composition is preferably 25-30%, whereas when the resin is an acrylic or methacryl resin, the co-solvent content of the composition is preferably 15-30%.

The composition may comprise minor metal compound additives, such as compounds of palladium (such as palladium sulfate), rhodium, bismuth or chromium which are generally used in admixture to improve the color, adhesion or gloss of burned coatings, especially in ceramics. have. In particular, the glassy minor metal compound additive may be, for example, a compound of silver, vanadium or silicon. Additives for glossy coatings are generally solutions of this composition. For example, the additive may be present as 0.01-5% generally 0.1-0.4% of the composition. The above additives, amounts and functions thereof are known per se for use in liquid noble metal compositions based on organic solvents.

Known minor metal additive compounds which are dissolved in current water and co-solvent mixtures are, for example, chromium trioxide or [Cr ₂ (SO ₄ ) ₃ ]; Ammonium bismuth citrate or bismuth lactate; [RhCl (ox) (NH ₃ )], [Rh (gly) ₃ ], [Rh ₂ (acetate) ₄ ], Na ₃ [Rh (NO ₃ ) ₆ ] or [Rh (acac) (CO)]; Me ₃ SiOMe; Or [VO (acac) ₂ ]: where acac represents acetylacetonate, ox represents oxalate and gly represents glycinato. In certain embodiments, they are used as thiolates, such as noble metals, which are rhodium, silver or bismuth such as AgN- (2-mercapto-propionyl) glycine. Thus, the thiolate of the noble metal is a gold compound of formula Au-SRX or a salt thereof and the rhodium minor metal additive may be of formula [Rh (SPX) ₃ ]. The composition should be homogeneous to facilitate application. In order to improve the rheology of the composition for application and to control the drying of the applied coating, the composition is for example a water miscible alcohol such as isopropanol or n-hexanol, such as a water miscible ketone such as butanone or 1,6-hexanediol Additional solvents such as water miscible solids may be included. The amount of additional solvent is preferably 5-10% of the composition. The composition may, for example, comprise as much as 0.05-0.5% of a surfactant to improve the brushing properties of the composition.

Characteristic composition according to the present invention consists essentially of the following components.

Preferred compositions according to the invention consist essentially of the following components.

The composition can be UV-curable because the polymer resin is UV-curable or can be thermally cured because the polymer resin is thermoset.

The composition is advantageous because it can be applied to and burned on a substrate in each known manner and its conventional equipment and techniques can be used. The substrate to be burned is preferably ceramic, such as porcelain, china or glass. The composition can be applied directly to the substrate. In addition, the composition is applied to a transfer substrate with a desired pattern (e.g., decorative pattern), dried to form a transfer pattern thereon, and the transfer pattern is a general method for transferring a pattern to a substrate such as a ceramic substrate which is burned. Used. The composition can be applied using a steel wheel or neoprene wheel, for example by brush or by eg ink jet printing (known as injection or injection print) but preferably screen printing. The particular composition and the specific composition in the composition for a particular application process depend on the particular application process in view of the desired fluidity. The applied composition is dried, for example, before burning at room temperature. However, it is dried as part of the heating process of combustion. The composition is generally burned at 200-900 ° C., for example at 460-650 ° C. on glass substrates, 650-900 ° C. on ceramic substrates and 200-350 ° C. on plastic substrates.

The composition forms an excellent coating. Precious metal coatings are divided into three grades: burnish self-burnish and bright.

Compositions for forming burnish coatings require burnishing to produce the desired coating, as its name suggests, and include precious metal powders or in some cases insoluble precious metal compounds. The burnt coating contains a heavier weight precious metal than the glossy coating, but the appearance is not shiny and no significant reflection is seen. After combustion they are burned with mechanical polishing, for example sand and water, to give a glossy appearance. Recently, self-burnished films have been introduced. These include insoluble matting agents, which provide the burned film with the durability and appearance of the burned film without the need for burnishing. The composition for forming the bright film contains a soluble noble metal compound. Burnt coatings are very reflective and often have mirror-like properties. The composition can be any of these types. Preferably, a glossy film is produced upon combustion. However, the composition may additionally comprise precious metal powders or insoluble precious metal compounds which produce a burnish coating on combustion and subsequent burnishing. Alternatively, the composition may additionally contain an insoluble varnish that burns upon combustion, producing a self-burned coating.

Current compositions can be preferably used to decorate a substrate, for example to decorate tableware. However, the composition can be used in electrical applications for the installation of electrical conductors in insulating materials.

The present invention is illustrated by the following examples wherein the rhodium complex is of the general formula Rh (acac) CO, where acac represents an acetylacetonate group and the polycellulose ether resin is "Natrasol" manufactured by AKK Corporation, and polymethacryl resin. Is “Versicol K 11” from Eryd Colloid, Inc., of Bradford, UK. Polyvinyl pyrrolidone is from Aldrich Chemicals, UK, and all other non-pointed compositions for encapsulation are solutions. Others are not described, but the compositions are applied on earthenware and then heated to the highest temperature of 780 ° C for 1 hour and soaked for 10 minutes at the maximum temperature.

Example 1

N- (2-mercaptopropionyl) glycine gold (I) is prepared in a two-necked 1000 ml round bottom flask as follows: A solution of sodium tetrachloroorate (35 g) in distilled water (200 ml) is distilled water. Add slowly to a solution of ethyl 2-hydroxyethyl sulfide (20.5 g) in (200 mL). Mercaptopropionyl glycine (5.21 g) was added as a solid and then vigorously stirred to give gold mercapto propionylglycine as a white solid (85% yield based on gold).

Comparative Example 1-3

In the same manner as in Example 1, the following was prepared:

Gold L-cysteine;

Gold 2-mercaptoethanesulfonic acid; And

Gold 2-mercaptopyridine;

> 80% each in gold based yield.

Comparative Example 4

Gold mercaptosuccinic acid was prepared in the same manner as in Example 1, except that isopropanol was used instead of water and the gold chloride was soluble in isopropanol, and the solvent was evaporated under reduced pressure (0.1 Torr) to liberate and then obtained The oil and diethyl ether are triturated to produce a white precipitate (greater than 80% yield based on gold).

Comparative Example 5

In the same manner as in Example 1, the following was prepared:

Gold 4-hydroxythiophenol (analysis of C: theoretical 22.3%

Found 21.8%)

> 80% yield based on gold.

Example 2

In the same manner as in Example 1, the followings were prepared.

Gold 4,6-dihydroxy-2- mercaptopyrimidine;

(Analysis of C: theoretical 13.9%

Found 13.2%)

> 80% yield based on gold.

Comparative Example 6

The components were mixed to obtain the following composition.

In these examples, parts by weight and the resin content is dry weight.

The composition is applied to a fryer and heated for 1 hour to a maximum temperature of 780 ° C. for 10 minutes. A matt and rough coating is obtained. The coating was not adhered and thus peeled off by normal rubbing.

The gold composition was not the gold thiolate of the present invention.

Comparative Example 7

The following composition was prepared and used in the same manner as in Comparative Example 6.

A matt and adhered film was obtained. The matteness of the coating is due to the fact that thiolate was previously decomposed during combustion to give an insoluble gold product.

Comparative Example 8-10

The composition was prepared and used in the same manner as Comparative Example 7 by replacing the gold thioleate of Comparative Example 7 with the following gold thiolate in an amount corresponding to 10 parts by weight of gold:

Gold cysteine (Comparative Example 8)

Gold mercaptobenzoic acid (Comparative Example 9)

Gold 2-mercaptopyridine (Comparative Example 10)

In each case, a matte film was obtained. The matteness of the coating was due to the pre-decomposition of thiolates upon combustion to provide insoluble gold products. The film was not adhered and thus peeled off with normal rubbing.

Comparative Example 11

The following composition was prepared and used in the same manner as in Comparative Example 6.

A matt and rough coating was obtained. The matteness of the coating is because thiolate is pre-decomposed during combustion to give insoluble gold product. The film was not adhered and thus peeled off with normal rubbing.

Example 3

The following composition was prepared and used in the same manner as in Comparative Example 6.

A glossy and adhered film was obtained.

It can be seen that the composition contains 10% gold as thiolate.

The composition can be applied to steel wheels and neoprene wheels. In both cases, this gives the same result as brushed and applied.

Example 4-6

The 1,3-propanediol of Example 3 was replaced with Example 3 by replacing 15 parts by weight of tetrahydrofuran acetate (Example 4), glycerol diacetate (Example 5) or ethyl lactate (Example 6). . In each case the resulting gold film was adhered and glossy.

Example 7-9

The following composition was prepared and used in the same manner as in Comparative Example 6.

In each case, a glossy and adherent film was obtained.

Comparative Example 12

The following composition was obtained and used in the same manner as in Comparative Example 6.

The composition was burned to obtain a matte and non-adhesive dull film. This is a result of low solubility of the gold compound during application of the composition and a heterogeneous composition is obtained upon heating. It is estimated that only about 5% of the gold mercaptide is dissolved in the original medium.

Comparative Example 13-19

The composition was prepared and substituted with the following one with respect to the gold composition, which was used in the method of Comparative Example 12.

13. Gold-5-mercapto-1-methyltetrazole

14. Gold-2-mercapto-5-nitrobenzimidazole

15. Gold-4-aminothiophenol

16. Gold-4-hydroxythiophenol

17. Gold-mercaptoacetic acid

18. Gold-2-mercaptopropionic acid

19. Gold-mercapto2,3-hydroxypropane

The film obtained was very unsatisfactory. The compositions of Comparative Examples 13-15 were unsatisfactory for the same reasons as Comparative Example 12 and resulted in a coating that was matt and especially had many recesses. The compositions of Comparative Examples 16-19 were previously decomposed into gold powder during preparation or during the use of the gold composition solution, resulting in a non-uniform composition. The gold compositions of Comparative Examples 16-19 and their general grades were unsatisfactory because they were organic based and therefore not effective for producing a glossy gold film from an aqueous medium.

Example 10

Aqueous solution gold compositions having a resin to solids ratio of 1:10 were prepared by mixing the following:

It can be seen that the composition contains 1.2% by weight of resin. The resulting coating was shiny and continuous, and the small amount of inorganic precipitate remaining on the coating was washed with water and then wiped with a tissue to dry.

Example 11

A composition was prepared and the gold compound was replaced with gold-acetyl cysteine and used as in Example 10. The result was the same.

Example 12

Gold- (γ-L-glutamyl-L-cysteinyl-glycine) Another name was prepared by mixing an aqueous solution gold composition comprising gold-glutathione by mixing the following.

The obtained film was shiny and continuous.

Example 13

Aqueous liquid gold compositions containing gold and palladium to have a burned metallic (grey) appearance were prepared by mixing the following:

ox = oxalate, polysulfide solution = water and 15% ammonium polysulfide solution from BDH UK. The film appearance obtained was glossy and continuous.

Example 14

Aqueous solution gold compositions suitable for fast and slow combustion cycles were prepared by mixing:

ox = oxalate; Bi-citrate is ammonium bismuth citrate from BDH UK. Polysulfide solution is the same as in Example 13.

Reflective and continuous coatings were made by the following combustion process:

Fast combustion: 40 minutes cycle; Maximum temperature = 805 ° C .; Install for 2 minutes.

Slow combustion: 200 ° C. per hour; Maximum temperature = 750 ° C .; Immerse for 10 minutes.

The same composition was applied to a magnetic container to produce a glossy and continuous coating with the same combustion cycle as in Comparative Example 6.

The composition applied to the magnetic container was polished by a cycle of immersion for 2 minutes for 40 minutes at a maximum temperature of 900 ° C to prepare a glossy and continuous film.

Example 15

Aqueous solution gold compositions suitable for application to glass containers were prepared by mixing the following.

The composition was applied to a glass container and soaked continuously for 10 minutes at 620 ° C., the highest temperature for a total of 1 hour. A glossy and continuous film was obtained.

Example 16

Aqueous solution gold compositions with high water concentrations and suitable for ink-jet printing were prepared by mixing the following:

The composition of Example 16 contains 61% water. The polyvinyl pyrrolidone resin has a molecular weight of 10,000 daltons. Polysulfide solution is the same as in Example 13. The composition was sprayed onto flat tiles with an ink-jet sprayer and burned to produce a shiny, continuous gold film.

Example 17

Aqueous solution gold compositions suitable for screen printing were prepared by mixing:

The composition contains 4.5% (solid content) of the resin. The composition was printed on tiles polished through a screen of mesh size 305μ. The burned coating was shiny and continuous. A small amount of inorganic precipitate remaining on the coating after combustion was washed with water and then wiped with a tissue to dry to give a glossy and continuous coating.

Example 18

Aqueous solution gold compositions containing gold powders for gloss effect and suitable for screen printing were prepared by mixing the following:

The composition is applied in the same manner as in Example 17. The obtained film was polished to give an off-bright gold effect.

Example 19

In the same manner for the composition of Example 19, burnishing burnish gold is prepared by simply reducing the polycellulose concentration to 25 parts by weight.

Example 20

Gold-N- (3-mercaptopropionyl) glycine was prepared in the same manner as in Example 1 with a yield exceeding 80% based on gold.

Analysis: Theory: C, 16.8 N, 3.9

Found: C 16.35 N, 3.55%

Claims (21)

In a homogeneous composition for burning and forming at least one precious metal film of platinum, palladium, gold and silver on a substrate, the composition consists of a polymer resin and a solution of a precious metal thiolate in water and a co-solvent, the composition comprising It contains 3-22% by weight of noble metals as thiolates, and the co-solvent, resin and thioleate are water evaporated as the composition on the substrate is dried and continuously heated to burn. A homogeneous composition, characterized by leaving the homogeneous composition followed by evaporation of the co-solvent to leave a homogeneous composition of thiolate in the resin and then decomposing the thiolate into a noble metal while the resin is volatilized. A composition for combusting and forming at least one precious metal film of platinum, palladium, gold, and silver on a substrate, the composition comprising a solution of polymer resin and precious metal thioleate in water and a co-solvent, wherein the composition is thiol 3-22% by weight of precious metals as a rate, and the co-solvent, resin and thioleate are water-evaporated as the composition on the substrate is dried, continuously heated and burned to give a solution of resin and thiolate in the co-solvent The co-solvent is evaporated to leave a thiolate solution in the resin, and then the thiolate is decomposed into precious metals while the resin is volatilized. The composition of claim 1 comprising 5-85% by weight of water. The composition of claim 1 wherein the precious metal comprises gold. 4. The composition of claim 3 wherein the precious metal comprises gold. The method according to claim 4 or 5, wherein X is a nitro group or a general formula -COOH, SO ₂ OH, -OH, -CO.NH ₂ , -NH ₂ or -OP (optionally substituted with a hydrogen atom). O) represents a group of (OH) ₂ , and R represents a divalent organic group. The gold compound of claim 6, wherein the gold compound of the general formula Au-S-R-H or Au-S-R-X is H-R-S-H or H-S-R-X is N- (2-mercaptopropionyl) glycine; N- (3-mercaptopropionyl) glycine; N- (20mercaptoacetyl) glycine; 2-mercaptoacetyl-L-histidine; 3-mercaptopropionyl-L-histidine; L-cysteine; Acetylcysteine; Or glutathione. The composition according to any one of claims 1 and 3 to 5, which contains 8-12% by weight of a noble metal as thiolate. 6. The composition of claim 1, wherein the resin consists mostly of polyvinylpyrrolidone, polymethacryl or polycellulose ether resins, the majority of which evaporate in the range of 200-500 ° C. 7. . The composition according to any one of claims 1 and 3 to 5, wherein the composition contains 5 to 4% by weight of the resin. 6. The composition of claim 1, wherein the co-solvent has a boiling point between 100 and 220 ° C. 7. 6. The composition of claim 1, wherein the co-solvent consists of water miscible precools, esters or ethers. 7. 13. The composition of claim 12, wherein the alcohol consists of 1,2-propanediol or 1,3-propanediol. The composition according to any one of claims 1 and 3 to 5, comprising 5-45% by weight of co-solvent. The composition according to any one of claims 1 and 3 to 5, which burns to produce a glossy coating. 6. The composition of claim 1, further comprising a precious metal powder or an insoluble precious metal compound to burn and then burnish to produce a burned coating. 7. 6. The composition of any one of claims 1 and 3 to 5, further comprising an insoluble varnish to burn to produce a self-burnish coating. 18. A transfer agent comprising the composition of any one of claims 1 to 17 dried thereon. A method of forming a noble metal film on a substrate, the method comprising applying the composition of any one of claims 1 to 17 onto a substrate and drying and burning the applied composition. 20. The method of claim 19, wherein the substrate on which the combustion is performed is ceramic or glass. 21. The method of claim 19 or 20, wherein the combustion temperature is 460-900 ° C.