US20210372100A1 - Device for water supply - Google Patents
Device for water supply Download PDFInfo
- Publication number
- US20210372100A1 US20210372100A1 US17/266,840 US201917266840A US2021372100A1 US 20210372100 A1 US20210372100 A1 US 20210372100A1 US 201917266840 A US201917266840 A US 201917266840A US 2021372100 A1 US2021372100 A1 US 2021372100A1
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- United States
- Prior art keywords
- water supply
- nickel
- nickel plating
- plating layer
- plating
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- 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.)
- Abandoned
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Classifications
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D3/00—Electroplating: Baths therefor
- C25D3/02—Electroplating: Baths therefor from solutions
- C25D3/12—Electroplating: Baths therefor from solutions of nickel or cobalt
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/627—Electroplating characterised by the visual appearance of the layers, e.g. colour, brightness or mat appearance
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D7/00—Electroplating characterised by the article coated
- C25D7/04—Tubes; Rings; Hollow bodies
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/10—Electroplating with more than one layer of the same or of different metals
- C25D5/12—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium
- C25D5/14—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium two or more layers being of nickel or chromium, e.g. duplex or triplex layers
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- E—FIXED CONSTRUCTIONS
- E03—WATER SUPPLY; SEWERAGE
- E03C—DOMESTIC PLUMBING INSTALLATIONS FOR FRESH WATER OR WASTE WATER; SINKS
- E03C1/00—Domestic plumbing installations for fresh water or waste water; Sinks
- E03C1/02—Plumbing installations for fresh water
- E03C1/04—Water-basin installations specially adapted to wash-basins or baths
Definitions
- the present invention relates to a technique to reduce leaching of nickel from a device for water supply including a nickel plating layer formed on a base material.
- devices for water supply that are used as a kitchen faucet, a laboratory faucet, a bath faucet, and other similar devices are made of, for example, a copper alloy from the viewpoints of corrosion resistance, processability, machinability, etc.
- This type of device for water supply is produced through a process in which a rough-formed copper alloy piece is cut and ground to be formed into a base material, and nickel plating is provided on the outer peripheral surface of the base material. In some cases, chrome plating is also provided on the nickel plating.
- the nickel plating layer may also be deposited on the inner surface of the device for water supply so as to have an overlay portion due to throwing power. Even if chrome plating is provided on the device for water supply, the chrome plating is unlikely to be deposited on the inner surface.
- the device 100 for water supply shown in FIG. 3 when the base material 101 comes into contact with water, nickel not only leaches from the base material 101 (which often contains nickel intentionally added for the purpose of increasing corrosion resistance or nickel as an unintentional impurity), but also from the overlay portion of the nickel plating layer 102 .
- an analysis of components of a cross section of an opening of a known device for water supply provided with nickel plating has demonstrated the following.
- the principal component (copper) of the base material 101 is detected at a high ratio, whereas negligible nickel is detected.
- nickel leaching from the overlay portion is detected at a high ratio.
- a technique is proposed to reduce an amount of nickel leaching from nickel plating provided on a device for water supply (in particular, the overlay portion) (see, for example, Patent Document 1).
- a sulfur component-containing organic additive is added to the nickel plating to impart gloss to the device for water supply, while chloral hydrate is added to reduce an amount of nickel leaching into tap water.
- chloral hydrate is added to a nickel plating processing solution to which the sulfur component-containing organic additive has been added, so that the nickel plating has a noble potential and the amount of nickel leaching from the nickel plating is reduced.
- the target values for water quality management provided in the Ministerial Ordinance are predicted to be regarded as water quality standards required for potable water.
- an amount of nickel (a leaching value of nickel) contained in potable water discharged from a device for water supply be not more than one-tenth of the value defined in the target-setting item for water quality management.
- the same or similar measures will be needed for tap water other than potable water.
- the nickel plating (hereinafter also referred to as “gloss nickel plating”) disclosed in Patent Document 1, to which the sulfur component-containing organic additive is added, can reduce an amount of leaching nickel to a limited extent.
- use of nickel plating to which no sulfur component-containing organic additive is added (hereinafter also referred to as “semigloss nickel plating”) can reduce an amount of leaching nickel, while making it difficult to attain sufficient gloss.
- the present invention related to a device for water supply including a nickel plating layer formed on a base material.
- the nickel plating layer contains no sulfur component.
- a corrosion potential of the nickel plating layer in a leach test liquid is ⁇ 0.01 V or greater with respect to a saturated calomel electrode as a reference.
- a surface of the nickel plating layer has a Wa value of 5.1 or less.
- the corrosion potential of the nickel plating layer in the leach test liquid is preferably +0.04 V or greater with respect to the saturated calomel electrode as the reference.
- the present invention provides a device for water supply which is glossy and from which a small amount of nickel leaches.
- FIG. 1 is a schematic view showing a device for water supply according to the present embodiment
- FIG. 2 is an exploded view of the device for water supply according to the present embodiment
- FIG. 3 is a schematic cross-sectional view illustrating a structure of the vicinity of an opening of the device for water supply according to the present embodiment
- FIG. 4 is a graph showing detection ratios of metals at an inner surface of an opening of a known device for water supply
- FIGS. 5A and 5B show representative results of analyses of Examples and Comparative Examples using an EPMA
- FIGS. 6A and 6B shows, on an enlarged scale, sulfur peaks in FIGS. 5A and 5B ;
- FIG. 7 shows a relationship between an appearance of a nickel plating layer and a Wa value (measured with WaveScan of BYK Japan KK) of a surface of the nickel plating layers of Examples and Comparative Examples;
- FIG. 8 shows potential-current curves and Ni leaching values of representative plating layers in a leach test liquid
- FIG. 9 shows a relationship between a corrosion potential and a nickel leaching value of representative nickel plating layers in a leach test liquid.
- FIG. 1 is a schematic view showing the faucet according to the present embodiment.
- FIG. 2 is an exploded view of the faucet according to the present embodiment.
- the faucet 1 according to the present embodiment is a common faucet (e.g., a kitchen faucet, a lavatory faucet, or a bath faucet) and configured to discharge tap water from a spout 30 .
- the faucet 1 includes a body 10 , legs 20 , and handles 50 .
- the term “device for water supply” has a meaning encompassing not only faucet parts such as a tap and a valve for supplying potable water, but also a joint and a water supply pipe.
- the “devices for water supply” are classified into “end-use water supply devices”, “water supply pipes”, “water supply devices disposed at middle positions of piping”, etc.
- the term “device for water supply” as used herein encompasses all of these devices and pipes.
- the “device for water supply” has an internal channel through which water passes and an exterior surface which does not contact with water.
- the present invention can be favorably provided as a faucet part.
- the body 10 is an example of the devices for water supply connectable to various devices for water supply.
- the body 10 includes a threaded portion 12 connectable to the leg 20 , a threaded portion 13 connectable to the spout 30 , and a threaded portion 14 connectable to the handle 50 via a spindle 40 .
- the leg 20 is an example of the devices for water supply connectable to the body 10 .
- the leg 20 has one end connected to a tap water supply source (not shown).
- the other end of the lag 20 has a nut 21 attached thereto.
- the nut 21 of the leg 20 is screwed onto the threaded portion 12 of the body 10 , so that the leg 20 is connected to the body 10 .
- the spout 30 is an example of the devices for water supply connectable to the body 10 .
- One end of the spout 30 has a nut 31 attached thereto, and the other end has an end sleeve 32 attached thereto.
- the nut 31 of the spout 30 is screwed onto the threaded portion 13 of the body 10 , so that the spout 30 is connected to the body 10 .
- the handle 50 is a part for adjusting a flow rate of water to be discharged.
- One end of the spindle 40 is attached to the handle 50 .
- the other end of the spindle 40 is screwed onto the threaded portion 14 of the body 10 , so that the handle 50 is connected to the body 10 via the spindle 40 .
- the body 10 , the leg 20 , the nut 21 , the spout 30 , the nut 31 , the end sleeve 32 , and the spindle 40 include a base material 101 and a nickel plating layer 102 formed on an outer peripheral surface of the base material 101 .
- the body 10 , the leg 20 , the nut 21 , the spout 30 , the nut 31 , and the end sleeve 32 include a chrome plating layer 103 formed on the nickel plating layer 102 .
- the body 10 , the leg 20 , the spout 30 , and other components have undergone lead removal treatment as necessary.
- FIG. 3 is a schematic view illustrating a structure of the device for water supply according to the present embodiment, specifically, a cross-sectional structure of an opening of the body 10 as the device for water supply.
- FIG. 4 is a graph showing detection ratios of metals at an inner surface of an opening of a known device for water supply.
- the device 100 for water supply includes the nickel plating layer 102 formed on the base material 101 .
- the nickel plating spreads to reach the water channel so as to have an overlay portion due to throwing power.
- the device 100 for water supply having this configuration when water flows in an F1 direction, nickel leaches not only from the base material 101 , but also from the overlay portion of the nickel plating layer 102 .
- the amount of nickel leaching from the base material 101 is less than the amount of nickel leaching from the overlay portion of the nickel plating layer 102 . Therefore, a reduction in the leaching of nickel from the device 100 for water supply requires a reduction in the leaching of nickel from the overlay portion of the nickel plating layer 102 . It would be conceivable to provide the chrome plating layer 103 on the nickel plating layer 102 . However, since the chrome plating layer 103 is unlikely to spread inward and does not contain nickel, the presence or absence of the chrome plating layer 103 has a small effect on the leaching of nickel.
- the base material 101 is made of, for example, a copper alloy.
- the nickel plating layer 102 is a layer formed on the base material 101 .
- the nickel plating layer 102 is formed on the base material 101 by using, for example, a plating solution having the composition and condition described below.
- the chrome plating layer 103 may be provided on the nickel plating layer 102 .
- a basic composition of the nickel plating solution which is the so-called Watts solution, includes nickel ions, chloride ions, sulfate ions, and boric acid.
- the basic composition includes, for example, 50 g/L of NiCl 2 .6H 2 O, 290 g/L of NiSO 4 .6H 2 O, and 40 g/L of H 3 BO 3 .
- the plating is formed under the conditions of a pH of about 4.0 and a temperature of about 55° C.
- organic additives sulfur-free salicylic acid, hexynediol, butynediol, propargyl alcohol, chloral hydrate, etc. can be used.
- a nickel plating layer contains no sulfur refers to a case where sulfur is not detected in an elementary analysis using an EMPA (e.g., an analysis method to be described later) performed on the nickel plating layer.
- the nickel plating layer that has been formed using the above-described plating solution has a corrosion potential of +0.04 V or greater with respect to a saturated calomel electrode (SCE) in a leach test liquid
- the amount of nickel leaching into tap water from the device for water supply can be reduced to no more than one-tenth of the value defined in the target-setting item for water quality management.
- the nickel plating layer 102 has a noble potential, and the leaching of nickel from the nickel plating layer 102 is further reduced.
- the amount of chloral hydrate contained in the plating solution is less than 0.8 g/L, it is difficult to reduce the leaching of nickel by the chloral hydrate alone.
- the nickel plating layer have a Wa value of 5.1 or less as measured with WaveScan manufactured by BYK Japan KK.
- the surface of the device 100 for water supply (the surface of nickel plating layer 102 ) is provided with gloss.
- addition of 0.8 g/L to 1.75 g/L of chloral hydrate to the plating solution makes the surface of the device 100 for water supply glossy.
- the amount of chloral hydrate in the plating solution exceeds 1.75 g/L, the surface of the device 100 for water supply becomes tarnished.
- the Wa value is measured with the WaveScan manufactured by BYK Japan KK.
- the device 100 for water supply can be produced which is glossy and from which a small amount of nickel leaches.
- the present embodiment exerts the following effects.
- the device for water supply according to the present embodiment is configured as the device 100 for water supply including the nickel plating layer 102 provided on the base material 101 .
- the nickel plating layer 102 contains no sulfur.
- a corrosion potential of the nickel plating layer 102 in the leach test liquid is ⁇ 0.01 V or greater with respect to a saturated calomel electrode as a reference.
- a surface of the nickel plating layer 102 has a Wa value (as measured with the WaveScan manufactured by BYK Japan KK) of 5.1 or less. This feature enables provision of the device 100 for water supply which is glossy and from which a small amount of nickel leaches.
- the corrosion potential of the nickel plating layer in the leach test liquid is preferably +0.04 V or greater with respect to the saturated calomel electrode as the reference. This feature makes it possible to reduce an amount of nickel leaching into tap water from the device for water supply to no more than one-tenth of the value defined in the target-setting item for water quality management.
- equivalent effects are exerted by application of the present invention to a device for water supply including a nickel plating layer having no chrome plating layer formed thereon.
- the body of the device for water supply may be subjected to lead removal treatment as necessary.
- Bodies of devices for water supply of Examples and Comparative Examples were produced according to plating condition Nos. 1 to 15 shown in.
- FIG. 5A shows a representative result of the analyses of the condition Nos. 2, 7, 8, 13, and 15 in which the plating solution contained saccharin.
- FIG. 5B shows a representative result of the analyses of the condition Nos. 1, 3 to 6, 9 to 12, and 14 in which the plating solution did not contain saccharin.
- FIG. 6A shows, on an enlarged scale, the peak of sulfur in FIG. 5A .
- FIG. 6B shows, on an enlarged scale, the peak of sulfur in FIG. 5B .
- the condition Nos. 2, 7, 8, 13, and 15 correspond to the so-called gloss nickel plating containing a sulfur component added thereto.
- the condition Nos. 1, 3 to 6, 9 to 12, and 14 correspond to the so-called semigloss nickel plating containing no sulfur component.
- the semigloss nickel plating which contains no sulfur component, allows a smaller amount of nickel to leach.
- the gloss of the surface of the body 10 for water supply increases with a decrease in the Wa value of the surface of the device 100 for water supply. Specifically, it has been confirmed that when the Wa value is 5.1 or less, the gloss of the surface is high enough so that device for water supply has an appearance suitable as a product. Further, it has been confirmed that when the Wa value of the surface is 3.6 or less, the device for water supply has gloss comparable to that of the gloss nickel plating.
- the devices for water supply produced using the Ni plating of the condition Nos. 1, 2, 5 to 8, and 12 were each subjected to the following conditioning and leach test in conformity with the method described in JIS S 3200-7 “Equipment for water supply service—Test methods of effect to water quality”.
- a leach test liquid at a temperature of about 23° C. was prepared.
- the inside of the device for water supply was filled with the leach test liquid and hermitically sealed. After the device for water supply was left standing for 2 hours, the liquid was disposed of. This operation was repeated four times.
- the device for water supply was filled with the leach test liquid and hermitically sealed. After the device for water supply was left standing for 16 hours, the liquid was disposed of.
- the device for water supply was filled with the leach test liquid and hermitically sealed. The device for water supply was then left standing for 16 hours, and all of the liquid was collected as a sample liquid.
- a nickel leaching value was determined for each of the nickel plating layers produced under the condition Nos. 1, 2, 5 to 8, and 12 (Example 1, Comparative Example 1, Examples 4 and 5, and Comparative Examples 2, 3, and 7). Note that since the different types of devices for water supply have different capacities, the leaching values were calculated according to a predetermined conversion formula. Subsequently, the following operations were carried out.
- a specimen was cut off from an inner portion of the body 10 of the device for water supply where the Ni plating was deposited.
- a copper-coated wire was bonded to the specimen, and then, the specimen was coated with an adhesive such that only the Ni plating was exposed, whereby specimen was formed into a sample electrode.
- the sample electrode, a platinum electrode (counter electrode), and a saturated calomel electrode as a reference electrode were placed in the leach test liquid.
- a potential-current curve of the sample electrode was determined using a potentiostat.
- a potential at which a current of 0.001 mA was observed was defined as a corrosion potential.
- a corrosion potential in the leach test liquid was determined for each of the plating layers of the condition Nos. 1, 2, 5 to 8, and 12 (Example 1, Comparative Example 1, Examples 4 and 5, and Comparative Examples 2, 3, and 7).
- FIG. 8 shows the potential-current curves and the Ni leaching values of the plating layers of Examples 1, 4, and 5, and Comparative Examples 1 to 3 and 7 measured in the leach test liquid.
- FIG. 9 shows a relationship between the corrosion potential and the nickel leaching value of the plating layers of Examples 1, 4, and 5, and Comparative Examples 1 to 3 and 7 measured in the leach test liquid.
- the nickel leaching value decreases with an increase in the corrosion potential of the nickel plating layer. Specifically, it has been confirmed that when the corrosion potential is ⁇ 0.01 V (with respect to the SCE) or greater, and preferably +0.02 V (with respect to the SCE) or greater, the nickel leaching value is reduced to lower than that of semigloss nickel plating that contains no chloral hydrate. Further, it has been confirmed that when the corrosion potential is +0.04 V (with respect to the SCE) or greater, the amount of nickel leaching into tap water from the device for water supply can be reduced to no more than one-tenth of the value defined in the target-setting item for water quality management.
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Abstract
The purpose of the present invention is to provide a tool for water supply, which has luster and rarely undergoes the leaching out of nickel. A tool for water supply 100 which is provided with a nickel-plated layer 102 formed on a base material 101, wherein the nickel-plated layer 102 contains no sulfur component, the corrosion potential of the nickel-plated layer 102 in a leaching solution as measured against a saturated calomel electrode is −0.01 or more (preferably +0.04 V or more), and the Wa value of the nickel-plated layer 102 as measured using a WaveScan device manufactured by BYK is 5.1 or less.
Description
- The present invention relates to a technique to reduce leaching of nickel from a device for water supply including a nickel plating layer formed on a base material.
- Conventionally, devices for water supply that are used as a kitchen faucet, a laboratory faucet, a bath faucet, and other similar devices are made of, for example, a copper alloy from the viewpoints of corrosion resistance, processability, machinability, etc. This type of device for water supply is produced through a process in which a rough-formed copper alloy piece is cut and ground to be formed into a base material, and nickel plating is provided on the outer peripheral surface of the base material. In some cases, chrome plating is also provided on the nickel plating.
- As shown in
FIG. 3 , in the vicinity of an opening of such a device for water supply provided with nickel plating, the nickel plating layer may also be deposited on the inner surface of the device for water supply so as to have an overlay portion due to throwing power. Even if chrome plating is provided on the device for water supply, the chrome plating is unlikely to be deposited on the inner surface. Referring to thedevice 100 for water supply shown inFIG. 3 , when thebase material 101 comes into contact with water, nickel not only leaches from the base material 101 (which often contains nickel intentionally added for the purpose of increasing corrosion resistance or nickel as an unintentional impurity), but also from the overlay portion of thenickel plating layer 102. - Specifically, as shown in
FIG. 4 , an analysis of components of a cross section of an opening of a known device for water supply provided with nickel plating has demonstrated the following. In a region inwardly distant by more than 15 mm from the end face of the opening (inner region of the device for water supply), the principal component (copper) of thebase material 101 is detected at a high ratio, whereas negligible nickel is detected. On the other hand, in a region inwardly extending over a distance of less than 15 mm from the end face of the opening (region close to the opening of the device for water supply), nickel leaching from the overlay portion is detected at a high ratio. - In view of this, a technique is proposed to reduce an amount of nickel leaching from nickel plating provided on a device for water supply (in particular, the overlay portion) (see, for example, Patent Document 1). According to the technique disclosed in
Patent Document 1, a sulfur component-containing organic additive is added to the nickel plating to impart gloss to the device for water supply, while chloral hydrate is added to reduce an amount of nickel leaching into tap water. According to this technique, chloral hydrate is added to a nickel plating processing solution to which the sulfur component-containing organic additive has been added, so that the nickel plating has a noble potential and the amount of nickel leaching from the nickel plating is reduced. - Meanwhile, water quality that tap water needs to maintain is determined by an Ordinance of the Ministry of Health, Labour, and Welfare, pursuant to the Water Supply Law. “Ministerial Ordinance on Water Quality Standards” enforced on Apr. 1, 2015 provides items of water quality standards and standard values (51 items). The Ministerial Ordinance also provides target-setting items for water quality management and target values (26 items), as a target of water quality that tap water should maintain. Nickel constitutes one item of the target-setting items for water quality management, and its target value is set to 0.02 mg/L.
- The target values for water quality management provided in the Ministerial Ordinance are predicted to be regarded as water quality standards required for potable water. In this case, it will be required that an amount of nickel (a leaching value of nickel) contained in potable water discharged from a device for water supply be not more than one-tenth of the value defined in the target-setting item for water quality management. The same or similar measures will be needed for tap water other than potable water.
- Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2015-212417
- However, the nickel plating (hereinafter also referred to as “gloss nickel plating”) disclosed in
Patent Document 1, to which the sulfur component-containing organic additive is added, can reduce an amount of leaching nickel to a limited extent. On the other hand, use of nickel plating to which no sulfur component-containing organic additive is added (hereinafter also referred to as “semigloss nickel plating”) can reduce an amount of leaching nickel, while making it difficult to attain sufficient gloss. - It is an object of the present invention to provide a device for water supply which is glossy and from which a small amount of nickel leaches.
- The present invention related to a device for water supply including a nickel plating layer formed on a base material. The nickel plating layer contains no sulfur component. A corrosion potential of the nickel plating layer in a leach test liquid is −0.01 V or greater with respect to a saturated calomel electrode as a reference. A surface of the nickel plating layer has a Wa value of 5.1 or less.
- The corrosion potential of the nickel plating layer in the leach test liquid is preferably +0.04 V or greater with respect to the saturated calomel electrode as the reference.
- The present invention provides a device for water supply which is glossy and from which a small amount of nickel leaches.
-
FIG. 1 is a schematic view showing a device for water supply according to the present embodiment; -
FIG. 2 is an exploded view of the device for water supply according to the present embodiment; -
FIG. 3 is a schematic cross-sectional view illustrating a structure of the vicinity of an opening of the device for water supply according to the present embodiment; -
FIG. 4 is a graph showing detection ratios of metals at an inner surface of an opening of a known device for water supply; -
FIGS. 5A and 5B show representative results of analyses of Examples and Comparative Examples using an EPMA; -
FIGS. 6A and 6B shows, on an enlarged scale, sulfur peaks inFIGS. 5A and 5B ; -
FIG. 7 shows a relationship between an appearance of a nickel plating layer and a Wa value (measured with WaveScan of BYK Japan KK) of a surface of the nickel plating layers of Examples and Comparative Examples; -
FIG. 8 shows potential-current curves and Ni leaching values of representative plating layers in a leach test liquid; and -
FIG. 9 shows a relationship between a corrosion potential and a nickel leaching value of representative nickel plating layers in a leach test liquid. - A preferred embodiment of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the following embodiment.
- First, a faucet produced by combining devices for water supply according to the present embodiment will be described as an example.
FIG. 1 is a schematic view showing the faucet according to the present embodiment.FIG. 2 is an exploded view of the faucet according to the present embodiment. As shown inFIGS. 1 and 2 , thefaucet 1 according to the present embodiment is a common faucet (e.g., a kitchen faucet, a lavatory faucet, or a bath faucet) and configured to discharge tap water from aspout 30. Thefaucet 1 includes abody 10,legs 20, and handles 50. In the present specification, the term “device for water supply” has a meaning encompassing not only faucet parts such as a tap and a valve for supplying potable water, but also a joint and a water supply pipe. The “devices for water supply” are classified into “end-use water supply devices”, “water supply pipes”, “water supply devices disposed at middle positions of piping”, etc. The term “device for water supply” as used herein encompasses all of these devices and pipes. Structurally speaking, the “device for water supply” has an internal channel through which water passes and an exterior surface which does not contact with water. The present invention can be favorably provided as a faucet part. - The
body 10 is an example of the devices for water supply connectable to various devices for water supply. Thebody 10 includes a threadedportion 12 connectable to theleg 20, a threaded portion 13 connectable to thespout 30, and a threadedportion 14 connectable to thehandle 50 via aspindle 40. - The
leg 20 is an example of the devices for water supply connectable to thebody 10. Theleg 20 has one end connected to a tap water supply source (not shown). The other end of thelag 20 has anut 21 attached thereto. Thenut 21 of theleg 20 is screwed onto the threadedportion 12 of thebody 10, so that theleg 20 is connected to thebody 10. - The
spout 30 is an example of the devices for water supply connectable to thebody 10. One end of thespout 30 has anut 31 attached thereto, and the other end has anend sleeve 32 attached thereto. Thenut 31 of thespout 30 is screwed onto the threaded portion 13 of thebody 10, so that thespout 30 is connected to thebody 10. - The
handle 50 is a part for adjusting a flow rate of water to be discharged. One end of thespindle 40 is attached to thehandle 50. The other end of thespindle 40 is screwed onto the threadedportion 14 of thebody 10, so that thehandle 50 is connected to thebody 10 via thespindle 40. - The
body 10, theleg 20, thenut 21, thespout 30, thenut 31, theend sleeve 32, and thespindle 40 include abase material 101 and anickel plating layer 102 formed on an outer peripheral surface of thebase material 101. In the present embodiment, thebody 10, theleg 20, thenut 21, thespout 30, thenut 31, and theend sleeve 32 include achrome plating layer 103 formed on thenickel plating layer 102. Thebody 10, theleg 20, thespout 30, and other components have undergone lead removal treatment as necessary. - Next, the device for water supply according to the present embodiment will be described.
FIG. 3 is a schematic view illustrating a structure of the device for water supply according to the present embodiment, specifically, a cross-sectional structure of an opening of thebody 10 as the device for water supply.FIG. 4 is a graph showing detection ratios of metals at an inner surface of an opening of a known device for water supply. - As shown in
FIG. 3 , thedevice 100 for water supply according to the present embodiment includes thenickel plating layer 102 formed on thebase material 101. In the opening of thedevice 100 for water supply, the nickel plating spreads to reach the water channel so as to have an overlay portion due to throwing power. In thedevice 100 for water supply having this configuration, when water flows in an F1 direction, nickel leaches not only from thebase material 101, but also from the overlay portion of thenickel plating layer 102. - As shown in
FIG. 4 , conventionally, the amount of nickel leaching from thebase material 101 is less than the amount of nickel leaching from the overlay portion of thenickel plating layer 102. Therefore, a reduction in the leaching of nickel from thedevice 100 for water supply requires a reduction in the leaching of nickel from the overlay portion of thenickel plating layer 102. It would be conceivable to provide thechrome plating layer 103 on thenickel plating layer 102. However, since thechrome plating layer 103 is unlikely to spread inward and does not contain nickel, the presence or absence of thechrome plating layer 103 has a small effect on the leaching of nickel. - In the present embodiment, the
base material 101 is made of, for example, a copper alloy. Thenickel plating layer 102 is a layer formed on thebase material 101. Thenickel plating layer 102 is formed on thebase material 101 by using, for example, a plating solution having the composition and condition described below. Thechrome plating layer 103 may be provided on thenickel plating layer 102. - A basic composition of the nickel plating solution, which is the so-called Watts solution, includes nickel ions, chloride ions, sulfate ions, and boric acid. Specifically, the basic composition includes, for example, 50 g/L of NiCl2.6H2O, 290 g/L of NiSO4.6H2O, and 40 g/L of H3BO3. The plating is formed under the conditions of a pH of about 4.0 and a temperature of about 55° C. As organic additives, sulfur-free salicylic acid, hexynediol, butynediol, propargyl alcohol, chloral hydrate, etc. can be used.
- The plating solution described above is free of sulfur-containing organic additives (e.g., saccharin). Consequently, the
nickel plating layer 102 of the present embodiment contains no sulfur. This feature reduces leaching of nickel from thenickel plating layer 102. In the present specification, “a nickel plating layer contains no sulfur” refers to a case where sulfur is not detected in an elementary analysis using an EMPA (e.g., an analysis method to be described later) performed on the nickel plating layer. - Further, if the nickel plating layer that has been formed using the above-described plating solution has a corrosion potential of +0.04 V or greater with respect to a saturated calomel electrode (SCE) in a leach test liquid, the amount of nickel leaching into tap water from the device for water supply can be reduced to no more than one-tenth of the value defined in the target-setting item for water quality management.
- Specifically, when 0.8 g/L or more (preferably 0.9 g/L or more) of chloral hydrate is added to the plating solution, the
nickel plating layer 102 has a noble potential, and the leaching of nickel from thenickel plating layer 102 is further reduced. On the other hand, when the amount of chloral hydrate contained in the plating solution is less than 0.8 g/L, it is difficult to reduce the leaching of nickel by the chloral hydrate alone. - Further, use of the plating solution described above makes the nickel plating layer have a Wa value of 5.1 or less as measured with WaveScan manufactured by BYK Japan KK. As a result, the surface of the
device 100 for water supply (the surface of nickel plating layer 102) is provided with gloss. Specifically, addition of 0.8 g/L to 1.75 g/L of chloral hydrate to the plating solution makes the surface of thedevice 100 for water supply glossy. On the other hand, when the amount of chloral hydrate in the plating solution exceeds 1.75 g/L, the surface of thedevice 100 for water supply becomes tarnished. Note that in the present specification, the Wa value is measured with the WaveScan manufactured by BYK Japan KK. - As can be seen, by a production method including forming plating on the
base material 101 using a nickel plating processing solution that is free of sulfur-containing organic additives and contains chloral hydrate in an amount of 0.8 g/L to 1.75 g/L, thedevice 100 for water supply can be produced which is glossy and from which a small amount of nickel leaches. - The present embodiment exerts the following effects. The device for water supply according to the present embodiment is configured as the
device 100 for water supply including thenickel plating layer 102 provided on thebase material 101. Thenickel plating layer 102 contains no sulfur. A corrosion potential of thenickel plating layer 102 in the leach test liquid is −0.01 V or greater with respect to a saturated calomel electrode as a reference. A surface of thenickel plating layer 102 has a Wa value (as measured with the WaveScan manufactured by BYK Japan KK) of 5.1 or less. This feature enables provision of thedevice 100 for water supply which is glossy and from which a small amount of nickel leaches. - The corrosion potential of the nickel plating layer in the leach test liquid is preferably +0.04 V or greater with respect to the saturated calomel electrode as the reference. This feature makes it possible to reduce an amount of nickel leaching into tap water from the device for water supply to no more than one-tenth of the value defined in the target-setting item for water quality management.
- Note that the present invention is not limited to the embodiment described above, but encompasses modifications and improvements made within the range in which the object of the present invention can be achieved.
- For example, equivalent effects are exerted by application of the present invention to a device for water supply including a nickel plating layer having no chrome plating layer formed thereon. The body of the device for water supply may be subjected to lead removal treatment as necessary.
- Bodies of devices for water supply of Examples and Comparative Examples were produced according to plating condition Nos. 1 to 15 shown in.
-
TABLE 1 Amount of Amount of Example/ Added Added Chloral Comparative Saccharin Hydrate Base Plating Example Condition (g/L) (g/L) Solution Example1 Condition — 0.9 Semigloss Ni No. 1 Plating Comparative Condition 5.0 1.0 Gloss Ni Plating Example1 No. 2 Example2 Condition — 0.2 Semigloss Ni No. 3 Plating Example3 Condition — 0.4 Semigloss Ni No. 4 Plating Examp1e4 Condition — 0.8 Semigloss Ni No. 5 Plating Example5 Condition — 1.25 Semigloss Ni No. 6 Plating Comparative Condition 5.0 — Ultra-Gloss Ni Example2 No. 7 Plating Comparative Condition 5.0 — Gloss Ni Plating Example3 No. 8 Comparative Condition — 1.8 Semigloss Ni Example4 No. 9 Plating Comparative Condition — 1.9 Semigloss Ni Example5 No. 10 Plating Comparative Condition — 2.0 Semigloss Ni Example6 No. 11 Plating Comparative Condition — — Semigloss Ni Example7 No. 12 Plating Comparative Condition 5.0 3.0 Gloss Ni Plating Example8 No. 13 Comparative Condition — — Semigloss Ni Example9 No. 14 Plating Comparative Condition 5.0 5.0 Gloss Ni Plating Example10 No. 15 - The bodies of the devices for water supply of Examples and Comparative Examples were each subjected to an analysis using an EPMA.
FIG. 5A shows a representative result of the analyses of the condition Nos. 2, 7, 8, 13, and 15 in which the plating solution contained saccharin.FIG. 5B shows a representative result of the analyses of the condition Nos. 1, 3 to 6, 9 to 12, and 14 in which the plating solution did not contain saccharin.FIG. 6A shows, on an enlarged scale, the peak of sulfur inFIG. 5A .FIG. 6B shows, on an enlarged scale, the peak of sulfur inFIG. 5B . - As shown in
FIGS. 5 and 6 , the condition Nos. 2, 7, 8, 13, and 15 correspond to the so-called gloss nickel plating containing a sulfur component added thereto. The condition Nos. 1, 3 to 6, 9 to 12, and 14 correspond to the so-called semigloss nickel plating containing no sulfur component. In comparison with the gloss nickel plating, the semigloss nickel plating, which contains no sulfur component, allows a smaller amount of nickel to leach. - Surfaces of the devices for water supply produced under condition Nos. 1 to 15 were visually observed. Among the devices for water supply, devices that were as glossy as or glossier than the device for water supply of the condition No. 8 (gloss nickel plating; Comparative Example 5) are marked with a circle (“∘”). The devices for water supply of the condition Nos. 12 and 14 (semigloss nickel plating containing no chloral hydrate) were not glossy, and the devices for water supply of the condition Nos. 9 to 11 had a tarnished surface. These devices for water supply were marked with a cross (“x”). A triangle (“Δ”) denotes devices for water supply having an intermediate degree of gloss between those marked with the circle (“∘”) and those marked with the cross (“x”). Further, the surface of each device for water supply was measured with the WaveScan of BYK Japan KK. A relationship between the appearance and the Wa value is shown in
FIG. 7 . - As shown in
FIG. 7 , it has been confirmed that the gloss of the surface of thebody 10 for water supply increases with a decrease in the Wa value of the surface of thedevice 100 for water supply. Specifically, it has been confirmed that when the Wa value is 5.1 or less, the gloss of the surface is high enough so that device for water supply has an appearance suitable as a product. Further, it has been confirmed that when the Wa value of the surface is 3.6 or less, the device for water supply has gloss comparable to that of the gloss nickel plating. - The devices for water supply produced using the Ni plating of the condition Nos. 1, 2, 5 to 8, and 12 were each subjected to the following conditioning and leach test in conformity with the method described in JIS S 3200-7 “Equipment for water supply service—Test methods of effect to water quality”.
- (1) The device for water supply was washed with tap water for 1 hour, and then, washed with water three times.
- (2) A leach test liquid at a temperature of about 23° C. was prepared. The inside of the device for water supply was filled with the leach test liquid and hermitically sealed. After the device for water supply was left standing for 2 hours, the liquid was disposed of. This operation was repeated four times.
- (3) The device for water supply was filled with the leach test liquid and hermitically sealed. After the device for water supply was left standing for 16 hours, the liquid was disposed of.
- (4) The operations (2) and (3) were repeated three times.
- (5) After the operation (2) was performed, the device for water supply was left standing for 64 hours, and then, the liquid was disposed of.
- (6) The operations (2) to (5) were performed once more.
- (7) The operations (2) to (4) were repeated three times, and thereafter, the operation (2) was carried out.
- (8) The device for water supply was filled with the leach test liquid and hermitically sealed. The device for water supply was then left standing for 16 hours, and all of the liquid was collected as a sample liquid.
- (9) A Ni concentration in the sample liquid was determined using a common inductively-coupled plasma emission spectrophotometry.
- (10) A calculation was performed using the Ni concentration of the sample liquid and a capacity of the tested device for water supply, so that the Ni concentration was converted to a Ni concentration in 1 L of water and a leaching value was determined. Note that the leach test liquid used in the leach test was specially prepared according to JIS S 3200-7.
- By way of the operations described above, a nickel leaching value was determined for each of the nickel plating layers produced under the condition Nos. 1, 2, 5 to 8, and 12 (Example 1, Comparative Example 1, Examples 4 and 5, and Comparative Examples 2, 3, and 7). Note that since the different types of devices for water supply have different capacities, the leaching values were calculated according to a predetermined conversion formula. Subsequently, the following operations were carried out.
- (11) A specimen was cut off from an inner portion of the
body 10 of the device for water supply where the Ni plating was deposited. A copper-coated wire was bonded to the specimen, and then, the specimen was coated with an adhesive such that only the Ni plating was exposed, whereby specimen was formed into a sample electrode. - (12) The sample electrode, a platinum electrode (counter electrode), and a saturated calomel electrode as a reference electrode were placed in the leach test liquid. A potential-current curve of the sample electrode was determined using a potentiostat. Here, a potential at which a current of 0.001 mA was observed was defined as a corrosion potential.
- By way of the above-described operations, a corrosion potential in the leach test liquid was determined for each of the plating layers of the condition Nos. 1, 2, 5 to 8, and 12 (Example 1, Comparative Example 1, Examples 4 and 5, and Comparative Examples 2, 3, and 7).
FIG. 8 shows the potential-current curves and the Ni leaching values of the plating layers of Examples 1, 4, and 5, and Comparative Examples 1 to 3 and 7 measured in the leach test liquid.FIG. 9 shows a relationship between the corrosion potential and the nickel leaching value of the plating layers of Examples 1, 4, and 5, and Comparative Examples 1 to 3 and 7 measured in the leach test liquid. - As shown in
FIG. 8 , it has been confirmed that the nickel leaching value decreases with an increase in the corrosion potential of the nickel plating layer. Specifically, it has been confirmed that when the corrosion potential is −0.01 V (with respect to the SCE) or greater, and preferably +0.02 V (with respect to the SCE) or greater, the nickel leaching value is reduced to lower than that of semigloss nickel plating that contains no chloral hydrate. Further, it has been confirmed that when the corrosion potential is +0.04 V (with respect to the SCE) or greater, the amount of nickel leaching into tap water from the device for water supply can be reduced to no more than one-tenth of the value defined in the target-setting item for water quality management. -
- 100: Device for Water Supply
- 101: Base Material
- 102: Nickel Plating Layer
Claims (9)
1. A device for water supply comprising a nickel plating layer formed on a base material,
wherein the nickel plating layer contains no sulfur component,
wherein a corrosion potential of the nickel plating layer in a leach test liquid is −0.01 V or greater with respect to a saturated calomel electrode as a reference, and
wherein a surface of the nickel plating layer has a Wa value of 5.1 or less as measured by BYK wave scan device.
2. The device for water supply according to claim 1 , wherein the corrosion potential of the nickel plating layer in the leach test liquid is +0.04 V or greater with respect to the saturated calomel electrode as the reference.
3. The device for water supply according to claim 1 , wherein the corrosion potential of the nickel plating layer in the leach test liquid is +0.02 V or greater with respect to the saturated calomel electrode as the reference.
4. The device for water supply according to claim 1 ,
wherein the surface of the nickel plating layer has a Wa value of 3.6 or less.
5. The device for water supply according to claim 2 ,
wherein the surface of the nickel plating layer has a Wa value of 3.6 or less.
6. The device for water supply according to claim 3 ,
wherein the surface of the nickel plating layer has a Wa value of 3.6 or less.
7. The device for water supply according to claim 1 ,
wherein the sulfur is not detected in an elementary analysis using an EPMA.
8. The device for water supply according to claim 2 ,
wherein the sulfur is not detected in an elementary analysis using an EPMA.
9. The device for water supply according to claim 3 ,
wherein the sulfur is not detected in an elementary analysis using an EPMA.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
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JP2018152107A JP7190280B2 (en) | 2018-08-10 | 2018-08-10 | plumbing fixtures |
JP2018-152107 | 2018-08-10 | ||
PCT/JP2019/020627 WO2020031462A1 (en) | 2018-08-10 | 2019-05-24 | Tool for water supply service |
Publications (1)
Publication Number | Publication Date |
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US20210372100A1 true US20210372100A1 (en) | 2021-12-02 |
Family
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US17/266,840 Abandoned US20210372100A1 (en) | 2018-08-10 | 2019-05-24 | Device for water supply |
Country Status (5)
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US (1) | US20210372100A1 (en) |
EP (1) | EP3835460A4 (en) |
JP (1) | JP7190280B2 (en) |
CN (1) | CN112601846A (en) |
WO (1) | WO2020031462A1 (en) |
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US5922478A (en) * | 1997-04-30 | 1999-07-13 | Masco Corporation | Article having a decorative and protective coating |
JP2005008900A (en) * | 2003-06-16 | 2005-01-13 | Toto Ltd | Method for reducing nickel elution from water supply equipment made of copper or copper alloy and the water supply equipment |
JP2006316480A (en) | 2005-05-12 | 2006-11-24 | Hayakawa Valve Seisakusho:Kk | Nickel-free water supply system |
JP6110049B2 (en) * | 2009-02-13 | 2017-04-05 | 日産自動車株式会社 | Chrome-plated parts and manufacturing method thereof |
JP5056889B2 (en) | 2010-03-31 | 2012-10-24 | 大日本印刷株式会社 | Foamed wallpaper with high adhesion between paper substrate and resin layer |
JP5869749B2 (en) * | 2010-03-31 | 2016-02-24 | Jx金属株式会社 | Manufacturing method of bright nickel plating material, and manufacturing method of electronic component using bright nickel plating material |
DE102014207778B3 (en) | 2014-04-25 | 2015-05-21 | Kiesow Dr. Brinkmann GmbH & Co. KG | Use of a mixture for use in a plating bath or plating bath to produce a bright nickel plating, and to a method of making an article having a bright nickel plating |
JP6498617B2 (en) | 2016-02-18 | 2019-04-10 | 奥野製薬工業株式会社 | Brightening agent for electro nickel plating, electro nickel plating solution, electro plating method, plated product, and nickel elution prevention method |
JP6542437B1 (en) | 2018-06-19 | 2019-07-10 | 奥野製薬工業株式会社 | Bright nickel plating method and control method of bright nickel plating film. |
-
2018
- 2018-08-10 JP JP2018152107A patent/JP7190280B2/en active Active
-
2019
- 2019-05-24 US US17/266,840 patent/US20210372100A1/en not_active Abandoned
- 2019-05-24 CN CN201980053087.XA patent/CN112601846A/en active Pending
- 2019-05-24 EP EP19846998.3A patent/EP3835460A4/en not_active Withdrawn
- 2019-05-24 WO PCT/JP2019/020627 patent/WO2020031462A1/en unknown
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EP3835460A4 (en) | 2021-08-11 |
JP2020026555A (en) | 2020-02-20 |
EP3835460A1 (en) | 2021-06-16 |
JP7190280B2 (en) | 2022-12-15 |
WO2020031462A1 (en) | 2020-02-13 |
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