US2907716A - Silver cleaner - Google Patents
Silver cleaner Download PDFInfo
- Publication number
- US2907716A US2907716A US2907716DA US2907716A US 2907716 A US2907716 A US 2907716A US 2907716D A US2907716D A US 2907716DA US 2907716 A US2907716 A US 2907716A
- Authority
- US
- United States
- Prior art keywords
- urea
- thiourea
- cleaning
- silver
- salt
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 229910052709 silver Inorganic materials 0.000 title claims description 10
- 239000004332 silver Substances 0.000 title claims description 10
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 title description 8
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 42
- 239000000203 mixture Substances 0.000 claims description 28
- 238000004140 cleaning Methods 0.000 claims description 24
- 150000003839 salts Chemical class 0.000 claims description 20
- 239000004202 carbamide Substances 0.000 claims description 12
- SQSPRWMERUQXNE-UHFFFAOYSA-N Guanylurea Chemical compound NC(=N)NC(N)=O SQSPRWMERUQXNE-UHFFFAOYSA-N 0.000 claims description 11
- 239000000126 substance Substances 0.000 claims description 7
- 229910001316 Ag alloy Inorganic materials 0.000 claims description 2
- 231100000252 nontoxic Toxicity 0.000 claims description 2
- 230000003000 nontoxic effect Effects 0.000 claims description 2
- UMGDCJDMYOKAJW-UHFFFAOYSA-N aminothiocarboxamide Natural products NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 37
- 239000000243 solution Substances 0.000 description 9
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 8
- 239000010949 copper Substances 0.000 description 8
- 239000002253 acid Substances 0.000 description 7
- 229910052802 copper Inorganic materials 0.000 description 7
- 239000004615 ingredient Substances 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 4
- 229910052976 metal sulfide Inorganic materials 0.000 description 4
- -1 organic acid salt Chemical class 0.000 description 4
- 238000005554 pickling Methods 0.000 description 4
- DZHMRSPXDUUJER-UHFFFAOYSA-N [amino(hydroxy)methylidene]azanium;dihydrogen phosphate Chemical compound NC(N)=O.OP(O)(O)=O DZHMRSPXDUUJER-UHFFFAOYSA-N 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- YBSLUBPQYDULIZ-UHFFFAOYSA-N oxalic acid;urea Chemical compound NC(N)=O.OC(=O)C(O)=O YBSLUBPQYDULIZ-UHFFFAOYSA-N 0.000 description 3
- 239000008247 solid mixture Substances 0.000 description 3
- 239000000080 wetting agent Substances 0.000 description 3
- LWFBRHSTNWMMGN-UHFFFAOYSA-N 4-phenylpyrrolidin-1-ium-2-carboxylic acid;chloride Chemical compound Cl.C1NC(C(=O)O)CC1C1=CC=CC=C1 LWFBRHSTNWMMGN-UHFFFAOYSA-N 0.000 description 2
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 2
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- BDHFUVZGWQCTTF-UHFFFAOYSA-M sulfonate Chemical compound [O-]S(=O)=O BDHFUVZGWQCTTF-UHFFFAOYSA-M 0.000 description 2
- 150000003585 thioureas Chemical class 0.000 description 2
- KNIKDPRISVIPBU-UHFFFAOYSA-N 1,2-dichloro-4-[isocyano-(4-methylphenyl)sulfonylmethyl]benzene Chemical compound C1=CC(C)=CC=C1S(=O)(=O)C([N+]#[C-])C1=CC=C(Cl)C(Cl)=C1 KNIKDPRISVIPBU-UHFFFAOYSA-N 0.000 description 1
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- CPGWILCKEJSITN-UHFFFAOYSA-N S(=O)(=O)(O)C1=C(C(=O)OCCCCCCCCCCCC)C=CC=C1.[Na] Chemical compound S(=O)(=O)(O)C1=C(C(=O)OCCCCCCCCCCCC)C=CC=C1.[Na] CPGWILCKEJSITN-UHFFFAOYSA-N 0.000 description 1
- 229910052946 acanthite Inorganic materials 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000004480 active ingredient Substances 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 150000001860 citric acid derivatives Chemical class 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- OKGXJRGLYVRVNE-UHFFFAOYSA-N diaminomethylidenethiourea Chemical class NC(N)=NC(N)=S OKGXJRGLYVRVNE-UHFFFAOYSA-N 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- 125000004177 diethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 239000000194 fatty acid Substances 0.000 description 1
- 229930195729 fatty acid Natural products 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- URXNVXOMQQCBHS-UHFFFAOYSA-N naphthalene;sodium Chemical compound [Na].C1=CC=CC2=CC=CC=C21 URXNVXOMQQCBHS-UHFFFAOYSA-N 0.000 description 1
- 150000003891 oxalate salts Chemical class 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 235000021317 phosphate Nutrition 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 125000005498 phthalate group Chemical group 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- XUARKZBEFFVFRG-UHFFFAOYSA-N silver sulfide Chemical compound [S-2].[Ag+].[Ag+] XUARKZBEFFVFRG-UHFFFAOYSA-N 0.000 description 1
- 229940056910 silver sulfide Drugs 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 150000003890 succinate salts Chemical class 0.000 description 1
- IIACRCGMVDHOTQ-UHFFFAOYSA-N sulfamic acid Chemical class NS(O)(=O)=O IIACRCGMVDHOTQ-UHFFFAOYSA-N 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 150000003672 ureas Chemical class 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
- C11D3/02—Inorganic compounds ; Elemental compounds
- C11D3/04—Water-soluble compounds
- C11D3/046—Salts
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
- C11D3/16—Organic compounds
- C11D3/26—Organic compounds containing nitrogen
- C11D3/32—Amides; Substituted amides
- C11D3/323—Amides; Substituted amides urea or derivatives thereof
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
- C11D7/02—Inorganic compounds
- C11D7/04—Water-soluble compounds
- C11D7/10—Salts
Definitions
- This invention relates to cleaning compositions for metals and it has"particu1ar relation to'compositions adapted to remove ,tarn'ish caused by sulfide and oxide films from metal surfaces, patricula'rly surfaces of silver, copper and their'alloys".
- V The main object of the present invention' is to provide a cleaning composition of the above" mentioned type r which is capable of efliciently removing. sulfide and oxide films from surfaces consisting of silver; copper and their alloys, without corrosion ofor other harmful influence on the metallic surface to be cleaned.
- Anotherobject of this invention is to carry out the cleaning operation without the escape of hydrogen sulfide into the atmosphere.
- Example 1 The following ingredients are mixedto form a uniform powder:
- the composition is preferably used in aqueous solution.
- aqueous solution For example 5 to 10 parts .by weight of the above comp'ositionare dissolvedin 60 parts by weight of Water and: the solution x is used as a cleaning composition for silver or copper.
- Example 3 Percent by weight Thiourea 40-60 Urea phosphate 30-50 Guanyl urea phosphate 5-10 are mixed to a uniform product, which can be used, for example, in aqueous solution containing 8 to 15% by Weight of the solid mixture.
- Any inorganic or organic acid salt of urea or guanyl 3 Y urea which is soluble in water, not oxidizing or toxic, and does not form water-insgluble salts with the metals to be removed, can be used,'e.g. sulfate salts, phosphates, oxalates, 'phthalates, :citrates, succinates, sulfamates and others.
- a mixture of difierent salts can also be used.
- wetting agents which can be used in carrying out the invention are sulfonated fatty-aclohols, sulfonated fatty acid esters, organic acid esters of diethyl ⁇ ene glycol, decyl-be nzene sodium sulfonate, sodium lauryl sulfobenzoate, alkyl naphthalene sodium sulfonate, sulfonated alkyl amides and the like.
- watersoluble salts of urea and/ or guanylurea with acids in which the ratio of urea or guanylurea to the acid is diflYerent from the ratios in the above forumlas, can also be used.
- composition according to the invention can be a salt of guanyl urea.
- a 4 V used also in paste form for example in the form of an aqueous paste.
- a cleaning composition for silver, copper and alloys of silver and copper consisting substantially of thiourea in mixture with-a water-soluble, non-toxic salt, which does not form a water-insoluble salt with silver and copper, of a substance selected from the group consisting ofurea and guanylurea.
- H S-binding substance is-a salt of guanylurea, said salt being capable of chemically reacting with H S evolved during cleaning with the composition.
- the cleaning composition of claim 1 in which the H s-binding substance is a mixture of a salt of urea with 6.
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Wood Science & Technology (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
- Detergent Compositions (AREA)
Description
United States Patent NoDrawinga Application May-8 ,-19 53 i Serial-No. 353,897
7 Claims; (Cl. 251- 152) This invention" relates to cleaning compositions for metals and it has"particu1ar relation to'compositions adapted to remove ,tarn'ish caused by sulfide and oxide films from metal surfaces, patricula'rly surfaces of silver, copper and their'alloys". V The main object of the present invention'is to provide a cleaning composition of the above" mentioned type r which is capable of efliciently removing. sulfide and oxide films from surfaces consisting of silver; copper and their alloys, without corrosion ofor other harmfulinfluence on the metallic surface to be cleaned.
Anotherobject of this invention is to carry out the cleaning operation without the escape of hydrogen sulfide into the atmosphere.
It has been known to use amixture of a colloid, such as evaporated cellulose pulp waste liquor, with diortholylthiourea for selectively controlling the action of an acid pickling bath on metals. Furthermore, it has been suggested previously to add to acid cleaning solutions a substituted thiourea containing a hydrogenated aryl group, as an inhibitor for the acid and it was known to use thioureas for dissolving silver sulfide, for example in the mirror industry. Finally, it has also been suggested to prepare cleaning compositions for silverand copper-containing surfaces, from thiourea and a water-soluble acid forming no water-insoluble compounds with copper and silver.
When thiourea is used in a cleaning and pickling solution, tarnish due to a metal sulfide is effectively removed. However, due to the chemical action of thiourea on the metal sulfide, hydrogen sulfide gas of offensive odor is released during this treatment. This tends to make metal cleaning operations using thiourea unpleasant, and if enough hydrogen sulfide gas is evolved, possibly dangerous.
It has now been found that this essential disadvantage of thiourea can be greatly reduced or eliminated by using a cleaning composition in which thiourea is present as an active ingredient in mixture with a salt of urea and/ or guanylurea wherein HX stands for one mol of the salt-forming acid. The salts of urea and/ or guanylurea used with thiourea according to the present invention have three functions: (a) upon dissolving the solid mixture in Water, they furnish the necessary acidity and form metal pickling and cleaning solutions, which are not corrosive; (b) the salts of urea and/ or guanylurea react with the hydrogen sulfide released in presence of metal sulfides in the cleaning solution and thus almost entirely prevent the escape of H 8 and the appearance of its unpleasant odor; (c) by the reaction of H 8 with the urea and/or guanylurea salts, the latter are converted into the corresponding salts of thiourea and/or guanylthiourea so that said reaction ,results in the formation of additional amounts of thiourea 2,907,716 Patented Oct. 6, 1959 2 compoundswhich supplement and strengthen the action of thiourea originally presentin the solution.
The reaction between H 8 and the salt of urea and guanylurearespectively, is apparently as follows: 1 nm nmnx +12ns nznc aNnmx 1120 Heating of the pickling and cleaning bath, for example from 50 to C, accelerates the above reactions.
Example 1 The following ingredients are mixedto form a uniform powder:
Percent by weight Thiourea 40-60 Urea phosphate 40-60 As an additional ingredient, l-5% by Weight of a conventional wetting agent can be incorporated in the composition.
The composition is preferably used in aqueous solution. For example 5 to 10 parts .by weight of the above comp'ositionare dissolvedin 60 parts by weight of Water and: the solution x is used as a cleaning composition for silver or copper.
i Example. 2
In order to prepare a cleaning solution for silver 10 to 15 parts of the following composition are dissolved in 60 parts of water:
Percent by Weight Thiourea 40-60 Urea oxalate 40-60 If desired, a wetting agent can be incorporated in this composition in the manner and amount stated in Example 1.
Example 3 Percent by weight Thiourea 40-60 Urea phosphate 30-50 Guanyl urea phosphate 5-10 are mixed to a uniform product, which can be used, for example, in aqueous solution containing 8 to 15% by Weight of the solid mixture.
Example 4 Percent by weight Thiourea 40-60 Urea oxalate 30-50 Guanyl urea sulfate 5-10 are homogeneously mixed and dissolved in water to form a solution containing 15 to 20% of the mixture.
It will be understood that this invention is not limited to the specific substances, proportions, procedures and other details specifically described above, and can be carried out with various modifications. Thiourea is the ac tive cleaning ingredient capable of dissolving the metal sulfides and must be present in the composition in an amount sufficient to act on the impurities to be removed. I have found that proportions of 40 to 60% of thiourea based on the weight of the total solid ingredients are satisfactory. On the other hand, the salt or salts of urea and/or guanylurea must be present in a concentration sufficient for reacting with the H S evolved during cleaning. I have found that this concentration should be in the range of 30 to 60% by weight based on the amount of total solid ingredients.
Any inorganic or organic acid salt of urea or guanyl 3 Y urea, which is soluble in water, not oxidizing or toxic, and does not form water-insgluble salts with the metals to be removed, can be used,'e.g. sulfate salts, phosphates, oxalates, 'phthalates, :citrates, succinates, sulfamates and others. A mixture of difierent salts can also be used. Examples of wetting agents which can be used in carrying out the invention are sulfonated fatty-aclohols, sulfonated fatty acid esters, organic acid esters of diethyl{ ene glycol, decyl-be nzene sodium sulfonate, sodium lauryl sulfobenzoate, alkyl naphthalene sodium sulfonate, sulfonated alkyl amides and the like.
The formul as ofthe salts described in the above .examples are:
Urea phosphate:
CO (fish- 13 4 Guanylurea phosphate:
Urea oxalate:
However, watersoluble salts of urea and/ or guanylurea with acids, in which the ratio of urea or guanylurea to the acid is diflYerent from the ratios in the aboveforumlas, can also be used.
The composition according to the invention can be a salt of guanyl urea. Y
, a 4 V used also in paste form, for example in the form of an aqueous paste.
What is claimed is:
1. A cleaning composition for silver, copper and alloys of silver and copper, consisting substantially of thiourea in mixture with-a water-soluble, non-toxic salt, which does not form a water-insoluble salt with silver and copper, of a substance selected from the group consisting ofurea and guanylurea. g
2; The cleaning-composition of claim 1, in which the ratio between thiourea and the ingredients for reacting with H S is in the'range of 30 to by weight.
3. The cleaning composition of claim 1, in which the H S-binding substance is a urea salt, said salt being capable of chemically reacting with-H 8 evolved during cleaning with the composition.
4. The cleaning composition of claim 1, in which the H S-binding substance is-a salt of guanylurea, said salt being capable of chemically reacting with H S evolved during cleaning with the composition.
'5. The cleaning composition of claim 1, in which the H s-binding substance is a mixture of a salt of urea with 6. The cleaning composition of claim 1, in the form of a solid mixture. I
7. The cleaning composition, of claim 1, in the form of an aqueous. solution.'
References Cited in the file of this patent UNITED STATES PATENTS
Claims (1)
1. A CLEANING COMPOSITION FOR SILVER, COPPER AND ALLOYS OF SILVER AND COPPER, CONSISTING SUBSTANTIALLY OF THIOSREA IN MIXTURE WITH A WATAER-SOLUBLE, NON-TOXIC SALT, WHICH DOES NOT FORM A WATER-INSOLUBLE SALT WITH SILVER AND COPPER, OF A SUBSTANCE SELECTEDFROM THE GROUP CONSISTING OF UREA AND GUANYLUREA.
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2907716A true US2907716A (en) | 1959-10-06 |
Family
ID=3448804
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US2907716D Expired - Lifetime US2907716A (en) | Silver cleaner |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2907716A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3041234A (en) * | 1958-12-30 | 1962-06-26 | Glidden Co | Metallic sulfide pigment |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2338987A (en) * | 1939-02-21 | 1944-01-11 | Watzel Rudolf | Preparation of nitrogen-phosphoric acid compounds for water softening |
| US2628199A (en) * | 1949-12-21 | 1953-02-10 | Frederick A Lowenheim | Tarnish remover |
-
0
- US US2907716D patent/US2907716A/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2338987A (en) * | 1939-02-21 | 1944-01-11 | Watzel Rudolf | Preparation of nitrogen-phosphoric acid compounds for water softening |
| US2628199A (en) * | 1949-12-21 | 1953-02-10 | Frederick A Lowenheim | Tarnish remover |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3041234A (en) * | 1958-12-30 | 1962-06-26 | Glidden Co | Metallic sulfide pigment |
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