Sanitary ware

Abstract

To provide sanitary ware having both excellent antifouling properties and high durability.SOLUTION: The sanitary ware comprises a sanitary ware substrate 1 and a glaze layer 2 provided on a surface of the substrate, and is characterized in that: a surface of the glaze layer has an arithmetic mean roughness Ra of 0.03 μm or more and 2.5 μm or less; a surface of the sanitary ware contains perfluoropolyether chains 3; a ratio of the number of oxygen atoms in the perfluoropolyether chains to a total number of carbon atoms having C-F bonds in the perfluoropolyether chains is 0.1 or more and 1.0 or less, which ratio is obtained through peak separation of a spectrum obtained through X-ray photoelectron spectroscopy (XPS) measurement of the surface of sanitary ware; and a ratio of the number of carbon atoms having CF3 bonds in the perfluoropolyether chains to the total number of carbon atoms having C-F bonds in the perfluoropolyether chains is 20 at% or less, which ratio is obtained through the peak separation.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to sanitary ware that is used in an environment where it may be splashed with water and has good stain resistance and high durability. [Background technology]

[0002] Components used in wet areas (so-called wet area components) are used in environments where water is present. Therefore, water easily adheres to the surfaces of wet area components. When this water that adheres to the surface dries, limescale containing silica and calcium, which are components found in tap water, forms on the surface of the wet area component. In addition, dirt such as proteins, sebum, microorganisms such as mold, and metal soaps also easily adhere to the surface of wet area components. In order to prevent the adhesion of dirt such as limescale to the surface of wet area components and to improve the removability of dirt, techniques are known for modifying the surface of the component by coating it with a protective layer, for example.

[0003] However, providing a protective layer on a wet-related component can cause discoloration of the component surface, or damage or peeling of the protective layer, impairing the component's appearance. To address this issue, monomolecular films that chemically bond with wet-related components have traditionally been used. Because monomolecular films are thin, invisible layers, providing a monomolecular film can impart the functionality of a monomolecular film without impairing the component's appearance. Furthermore, because the monomolecular film chemically bonds with the wet-related component, its durability is also improved. For example, monomolecular films containing fluoroalkylsilane compounds are known to protect the component surface and also have antifouling properties. For example, Japanese Patent Laid-Open Publication No. 2005-206455 (Patent Document 1) describes how abrasion-resistant, antifouling ceramic products can be obtained by forming a film containing a fluoroalkylsilane compound on the surface of a tile.

[0004] On the other hand, it is difficult to completely prevent dirt from adhering to the surface of wet-related components, and dirt is removed by cleaning. For example, in the case of sanitary ware, attempts have been made to improve the smoothness of the surface to make dirt easier to remove. However, adhesion of dirt can roughen the surface and reduce its hydrophilicity. Sanitary ware that can easily remove such adhered dirt remains in demand. Removing adhered dirt and limescale often requires the use of strong alkaline or acidic detergents, or requires increased wiping force or repeated wiping. In other words, wet-related components are subjected to high-stress environments. As a result, thin films such as the monomolecular film containing the above-mentioned fluoroalkylsilane compound can quickly lose their functionality. Therefore, in recent years, a technology has been proposed in which compounds containing perfluoropolyether chains, which have superior adhesion and durability to wet-related components compared to fluoroalkylsilane compounds, are applied to the surface of components.

[0005] For example, Japanese Patent Laid-Open No. 2011-021088 (Patent Document 2) describes forming an antifouling layer by applying an antifouling coating material containing a perfluoropolyether as a base agent and an alkane with a specific average molecular weight as a solvent to the surface of sanitary ware having a glaze layer. According to Patent Document 2, the perfluoropolyether contains a CF3 side chain (paragraphs 0013-0014), and applying an antifouling coating material containing this perfluoropolyether and an alkane with a specific average molecular weight forms an antifouling layer with excellent smoothness (paragraph 0016).

[0006] Furthermore, Japanese Patent Application Laid-Open No. 2021-113323 (Patent Document 3) describes that a hardened layer having good friction durability is formed by applying a surface treatment agent containing a perfluoropolyether group-containing compound to the surface of chemically strengthened glass. Specifically, -(OC6F 12 ) a -(OC5F 10 ) b -(OC4F8) c -(OC3F6) d -(OC2F4) e -(OCF2)f In paragraph 0039, it is stated that the e / f ratio must be 0.9 or higher, which increases the water and oil repellency of the cured layer. On the other hand, if the e / f ratio is too low, the lubricity (surface slipperiness) of the cured layer decreases, and if the e / f ratio is too high, the dynamic friction coefficient of the cured layer increases, making it impossible to obtain sufficient friction durability. More specifically, it is preferable that the e / f ratio is 1.0 or higher (paragraph 0039), and in the [Examples], it is stated that the cured layers formed by applying the surface treatment agents of Examples 1, 2, and 3, which contain perfluoropolyether group-containing compounds with e / f ratios of 1.08, 1.03, and 1.08, respectively, showed good results in an eraser abrasion resistance test. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-206455 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-021088 [Patent Document 3] Japanese Patent Publication No. 2021-113323 Summary of the Invention [Problem to be solved by the invention]

[0008] The inventors have confirmed that even among sanitary ware whose surfaces contain perfluoropolyether chains, which are generally considered to have high durability, some lose their functionality when used under high-stress conditions. They have now discovered a new configuration for sanitary ware that combines good stain resistance with greater durability, particularly abrasion resistance. Specifically, they have found that the unique textured surface of sanitary ware, when equipped with specific perfluoropolyether chains, can effectively prevent the adhesion of stains and can easily remove even stains that would normally require cleaning under high-stress conditions, i.e., with a small cleaning load. Furthermore, they have found that sanitary ware can be obtained that has high durability, particularly abrasion resistance, against the cleaning load required for stain removal. The present invention is based on these findings. [Means for solving the problem]

[0009] The sanitary ware according to the present invention is The sanitary ware comprises a base material for sanitary ware and a glaze layer provided on the surface of the base material, The glaze layer has an arithmetic mean roughness Ra of its surface of 0.03 μm or more and 2.5 μm or less, the surface of the sanitary ware contains perfluoropolyether chains, the ratio of the number of oxygen atoms in the perfluoropolyether chain to the number of all carbon atoms having C-F bonds in the perfluoropolyether chain, which is obtained by peak separation of a spectrum obtained by measuring the surface of the sanitary ware by X-ray photoelectron spectroscopy (XPS), is 0.1 or more and 1.0 or less, The ratio of the number of carbon atoms having a C—F bond in the perfluoropolyether chain to the total number of carbon atoms having a C—F bond in the perfluoropolyether chain, obtained by the peak separation, is 20 at % or less. [Effects of the Invention]

[0010] According to the present invention, by providing specific perfluoropolyether chains on the surface of a glaze layer having a specific surface roughness, a sanitary ware is provided that has excellent durability against sliding force and can maintain good stain resistance even when used in a high-stress environment (an environment in which strong alkaline or strong acid detergents are used to remove stains, wiping is done with strong force, or wiping is done frequently).In addition, according to the present invention, a sanitary ware is provided that combines the above-mentioned good stain resistance and high durability while maintaining a beautiful appearance that makes use of the properties unique to sanitary ware (e.g., texture, gloss, hardness, etc.). [Brief explanation of the drawings]

[0011] [Figure 1] 1A and 1B are a schematic view and an enlarged view showing an example of sanitary ware according to the present invention. [Figure 2] 1A and 1B are schematic diagrams of the surface of a sanitary ware before and after a load is applied to the surface. [Figure 3] FIG. 1 shows the XPS spectrum and peak separation results for the surface of sanitary ware produced using treatment liquid a. [Figure 4] FIG. 10 shows the XPS spectrum and peak separation results for the surface of sanitary ware produced using treatment liquid b. [Figure 5] FIG. 10 shows the XPS spectrum and peak separation results for the surface of sanitary ware produced using treatment liquid c. [Figure 6] FIG. 10 shows the XPS spectrum and peak separation results for the surface of sanitary ware produced using treatment liquid d. [Figure 7] FIG. 10 shows the XPS spectrum and peak separation results for the surface of sanitary ware produced using treatment liquid e. [Figure 8] FIG. 10 shows the XPS spectrum and peak separation results for the surface of sanitary ware prepared using treatment liquid f. [Figure 9] FIG. 10 shows the XPS spectrum and peak separation results for the surface of sanitary ware produced using treatment solution g. DETAILED DESCRIPTION OF THE INVENTION

[0012] Sanitary ware In the present invention, "sanitary ware" refers to ceramic products used in bathrooms, toilet spaces, dressing rooms, washrooms, kitchens, etc. Specifically, it refers to toilet bowls, urinals, toilet sinks, toilet tanks, washbasins, hand basins, etc.

[0013] Fig. 1A is a schematic diagram showing the cross-sectional structure of sanitary ware according to the present invention, and Fig. 1B is an enlarged view of the circled portion in Fig. 1A. As shown in Fig. 1A, sanitary ware 10 according to the present invention comprises a sanitary ware base 1 and a glaze layer 2. The sanitary ware 10 includes perfluoropolyether chains 3 on the surface of the glaze layer 2.

[0014] Base for sanitary ware In the present invention, the sanitary ware body 1 is not particularly limited, and any known sanitary ware body used for the sanitary ware 10 can be used. The sanitary ware body 1 may be any conventionally known sanitary ware body obtained by preparing, molding, and firing silica sand, feldspar, limestone, clay, or the like as raw materials.

[0015] In one embodiment of the present invention, an intermediate layer made of another base material having properties different from those of the sanitary ware base material 1 may be provided between the glaze layer 2 and the sanitary ware base material 1. This can prevent air bubbles from penetrating into the glaze layer 2 from the sanitary ware base material during the firing process during production, and can form a glaze layer 2 that is not only excellent in appearance but also in cleanability.

[0016] Glaze layer In the present invention, the arithmetic mean linear roughness Ra of the surface of the glaze layer 2 is 0.03 μm or more and 2.5 μm or less. Preferably, the arithmetic mean linear roughness Ra of the surface of the glaze layer 2 is 0.03 μm or more and 1.5 μm or less. More preferably, the arithmetic mean linear roughness Ra of the surface of the glaze layer 2 is 0.03 μm or more and 1.0 μm or less. The arithmetic mean linear roughness Ra is measured in accordance with "7. Evaluation Methods and Procedures Using a Stylus Surface Roughness Meter" of JIS-B0633 (2001) using a stylus surface roughness measuring device conforming to JIS-B0651 (2001). In the present invention, the arithmetic mean linear roughness Ra of the surface of the glaze layer 2 is considered to be the same as the arithmetic mean linear roughness Ra of the surface of the sanitary ware 10. Therefore, the arithmetic mean linear roughness Ra of the glaze layer 2 can be determined by measuring the arithmetic mean linear roughness Ra of the surface of the sanitary ware 10. The reason for this is that the perfluoropolyether chains 3 contained in the surface of the sanitary ware 10 have a height that does not affect the surface roughness of the glaze layer 2. Specifically, the perfluoropolyether chains 3 preferably have a height of 20 nm or less. In the present invention, the glaze layer 2 may have a composition that is generally understood by those skilled in the art as a glaze layer, as long as its surface satisfies the above Ra. According to one embodiment of the present invention, the glaze layer 2 has a composition, converted into oxides, shown in Table 1 below.

[0017] [Table 1]

[0018] According to another embodiment of the present invention, the glaze layer 2 may contain Fe2O3, TiO2, BaO, BO3, Li2O, Sb2O3, CuO, MnO, NiO, CoO, MoO3, SnO2, PbO, etc. in addition to the components listed in Table 1 above. The glaze layer 2 may also contain particles. These particles include crystalline particles contained in the glaze raw materials and crystalline particles precipitated by firing. Examples of particle materials include zircon, quartz, diopside, and anorthite.

[0019] In the present invention, the color of the glaze layer 2 is not particularly limited as long as the composition of the glaze layer 2 is within the range of Table 1. Examples of the color of the glaze layer 2 include white, black, ivory, pink, gray, brown, beige, green, red, and blue.

[0020] In the present invention, the arithmetic mean roughness Ra (0.03 μm or more and 2.5 μm or less) of the surface of the glaze layer 2 may be such that Ra falls within the above range by processing the surface of the glaze layer 2, or the surface of the base 1 for sanitary ware may be processed so that Ra of the glaze layer 2 thereon falls within the above range.

[0021] In the present invention, a primer layer may be provided on the surface of the glaze layer 2. By providing a primer layer, it is possible to form perfluoropolyether chains at a high density on the surface of the glaze layer. The primer layer preferably does not affect the Ra of the surface of the glaze layer 2, and its thickness is preferably on the nanometer order. Specifically, it is 20 nm or less, and more preferably 10 nm or less. The primer layer is preferably a layer containing a metal oxide such as SiO2, TiO2, or Al2O3 that is generated by hydroxyl groups present on the surface.

[0022] Sanitary ware manufacturing In the present invention, the sanitary ware 10 can be produced, for example, by first forming a glaze layer 2 on a base 1 for the sanitary ware, and then applying a treatment liquid containing a compound having a perfluoropolyether chain 3 to the surface of the glaze layer 2. Specifically, it can be produced by the following method.

[0023] First, a molded body that will become the base material 1 for the sanitary ware is prepared. This is made by casting a conventionally known sanitary ware slurry prepared from raw materials such as silica sand, feldspar, limestone, and clay into a mold made of plaster or the like. After drying, the molded body is glazed as described below.

[0024] The glaze materials forming the glaze layer 2 are not particularly limited as long as they can achieve an arithmetic mean linear roughness (Ra) of the surface of the glaze layer 2 of 0.03 μm to 2.5 μm, but may be those capable of achieving the glaze layer composition shown in Table 1 above. The glaze materials may also include mixtures of natural mineral particles such as silica sand, feldspar, and limestone, pigments such as cobalt compounds and iron compounds, and opacifiers such as zirconium silicate and tin oxide. In one embodiment of the present invention, the glaze materials may have a composition of, for example, 10 wt% to 30 wt% feldspar, 15 wt% to 40 wt% silica sand, 10 wt% to 25 wt% calcium carbonate, 10 wt% or less each of corundum, talc, dolomite, and zinc oxide, and a total of 15 wt% or less of opacifiers and pigments. The glaze can be obtained, for example, by melting the glaze materials described above at high temperature and then rapidly cooling them to vitrify them.

[0025] The above-described glaze is applied to the dried molded body, and then dried and fired to form a glaze layer 2 on the sanitary ware base 1. The firing temperature can be, for example, 1000°C or higher and 1300°C or lower, at which the glaze softens.

[0026] The surface of the formed glaze layer 2 may be subjected to a surface treatment as needed, provided that the Ra satisfies the aforementioned range. For example, blasting or etching may be performed. In blasting, the surface of the glaze layer 2 can be obtained with an Ra that satisfies the aforementioned range by controlling the material, shape, and particle size of the media used, the processing time per unit area, whether the processing is dry or wet, and the like. In etching, the surface of the glaze layer 2 can be obtained with an Ra that satisfies the aforementioned range by controlling the photomask pattern and the concentration, type, temperature, and presence or absence of stirring of the etching solution. This can improve the glossiness of the surface or reduce the glossiness to create a matte finish.

[0027] The surface of the formed glaze layer 2 may have micro-roughness in a range where Ra satisfies the aforementioned range. For example, when observed using a scanning probe microscope (SPM), the arithmetic mean surface roughness Sa at a field of view of 5.0 μm × 5.0 μm is preferably 0.03 μm or less. The arithmetic mean surface roughness Sa of the surface of the glaze layer 2 is measured in accordance with JIS-B0681-2 (2018) using a coordinate measuring machine described in JIS-B0681-6 (2014). If the perfluoropolyether chains 3 provided on the surface of the glaze layer 2 having such micro-roughness Sa are highly flexible, the chains 3 can not only conform to a surface shape where Ra satisfies the aforementioned range, but also conform to a surface shape with micro-roughness in a micro-region. This is thought to result in a sanitary ware with excellent abrasion resistance and resistance to alkaline components contained in detergents and the like (hereinafter referred to as alkali resistance). It is also thought that the presence of microscopic roughness in the microscopic regions can further improve water repellency, resulting in better stain resistance.

[0028] In the present invention, in addition to the above-described methods for manufacturing a sanitary ware base and a glaze layer, methods for manufacturing a sanitary ware base and a glaze layer described in, for example, JP 2021-134133 A, JP 2020-147492 A, WO99 / 61392 A, etc. can be used. In this specification, by referring to the above publications, the methods for manufacturing a sanitary ware base and a glaze layer described therein are incorporated into the description of this specification as methods for manufacturing a sanitary ware base and a glaze layer that can be used in the present invention.

[0029] Next, a treatment liquid containing a compound containing perfluoropolyether chain 3, which will be described later, is applied to the surface of the glaze layer 2 formed on the sanitary ware base 1. The treatment liquid containing the compound containing perfluoropolyether chain 3 can be applied by any known method. For example, the treatment liquid containing the compound containing perfluoropolyether chain 3 can be applied by dipping, spin coating, wiping, vacuum deposition, spray gun, or the like. After the treatment liquid containing the compound containing perfluoropolyether chain 3 is applied to the surface of the glaze layer 2, it is dried and cured as necessary. Thereafter, optionally and preferably, the surface of each sanitary ware is washed with a neutral detergent and a sponge, followed by thorough rinsing with ultrapure water, thereby obtaining sanitary ware 10 containing perfluoropolyether chain 3 on the surface of the glaze layer 2.

[0030] In the present invention, a pretreatment may be performed to remove dirt present on the surface and activate the hydroxyl groups on the surface before applying a treatment liquid containing a compound having a perfluoropolyether chain 3 to the surface of the glaze layer 2. Examples of pretreatments that can be used to activate the hydroxyl groups on the surface include ultrasonic cleaning using an alkaline solution and particle polishing using metal fine particles.

[0031] In the present invention, a primer layer may be formed on the surface of the glaze layer 2, and after performing pretreatment as necessary, a treatment liquid containing a compound having a perfluoropolyether chain 3 may be applied. The primer layer may be formed by, for example, a sol-gel method, a physical vapor deposition method (PVD), a chemical vapor deposition method (CVD), or the like.

[0032] Any treatment solution containing a compound having a perfluoropolyether chain 3 can be used as long as it can produce the sanitary ware of the present invention. Examples of compounds containing perfluoropolyether chain 3 include compounds containing a chain in which one or more ether bonds, which are repeating units such as CFO, CFO, CFO, and CFO, are randomly bonded. Specific examples of compounds containing perfluoropolyether chain 3 include compounds having the structure shown in Formula 1 below. [ka] Here, p, q, r, and s are the numbers of repeating units, i.e., integers of 0 or more, and the sum of p, q, r, and s is 3 to 200. The repeating units in the formula may be randomly bonded to form a chain, or polymer chains each made of the repeating units may be bonded to each other. f1 represents a fluorine atom or an organic group having one or more carbon atoms containing a carbon atom to which a fluorine atom is singly bonded, and R f2 represents an organic group having one or more carbon atoms, including a carbon atom to which a fluorine atom is singly bonded.

[0033] Further specific examples of compounds containing the perfluoropolyether chain 3 include compounds containing structures shown in the following formulas 2 to 6. [ka] (In the formula, l:m:n=23.2:22.3:0.4 (average value), and the repeating units in the formula are arranged randomly.) [ka] (wherein the average value of l is 22.9), [ka] (wherein the average value of l is 23.2), [ka] (wherein the average value of l is 18), [ka] (where the average value of l is 23.4).

[0034] The compound containing the perfluoropolyether chain 3 is preferably a compound containing the perfluoropolyether chain 3 and at least one Si atom. It is more preferable that the perfluoropolyether chain 3 is bonded to at least one reactive silyl group. This facilitates bonding between the surface of the glaze layer 2 and the perfluoropolyether chain 3. The Si atom of the reactive silyl group may be bonded to one end of the perfluoropolyether chain 3 or to both ends, but is preferably bonded to one end. The reactive silyl group is a functional group in which an organic group containing no fluorine atom in the Si atom is bonded to a hydroxyl group or a hydrolyzable group. Specific examples of the hydrolyzable group include alkoxy groups and halogeno groups, and more specifically, -OCH3, -OCH2CH3, -OCOCH3, -Cl, etc.

[0035] The solvent used in the treatment liquid may be any solvent that is miscible with the perfluoropolyether chain 3, and examples thereof include fluorine-based solvents, hexane, chain ether compounds, and cyclic ether compounds.

[0036] Perfluoropolyether Chain The surface of the sanitary ware 10 according to the present invention contains a perfluoropolyether chain 3. The perfluoropolyether chain 3 is a chain containing, in its repeating structure, a carbon atom to which a fluorine atom is bonded and an ether bond to which the carbon atom is bonded via an oxygen atom, and for example, -[(CF2) x It contains a repeating unit represented by the formula: [—O]-(x is a natural number). Specifically, it is a chain in which one or more ether bonds, which are repeating units such as (CF2)—O, (C2F4)—O, (C3F6)—O, and (C4F8)—O, are randomly bonded. In the present invention, the total number of repeating units is preferably large, but is more preferably 200 or less.

[0037] The presence of the perfluoropolyether chains 3 on the surface of the sanitary ware 10 can be identified, for example, by the following analytical method.

[0038] The presence of perfluoropolyether chains 3 on the surface of the sanitary ware 10 can be identified by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS).

[0039] First, the surface of the sanitary ware is evaluated using X-ray photoelectron spectroscopy (XPS), and C1s and F1s spectra are obtained. In these spectra, the peaks of fluorine atoms with C-F bonds in F1s (peak position: 687 eV to 690 eV) and carbon atoms with C-F bonds in C1s (peak position: 289 eV to 297 eV) are observed, indicating that the sanitary ware surface contains C-F bonds. Examples of compounds containing C-F bonds include perfluoropolyether chain-containing compounds and fluoroalkylsilane compounds. The XPS measurements are performed using the "XPS measurement conditions" described below under "Acquisition of XPS spectra."

[0040] The surface of the sanitary ware is then evaluated using TOF-SIMS. The TOF-SIMS device used can be the TOF.SIMS5 (ION-TOF). TOF-SIMS is an analytical technique that detects secondary ions generated from a sample surface when the surface is irradiated with pulsed primary ions emitted from a primary ion source. The type of secondary ions generated and the detection sensitivity vary depending on the composition and chemical structure of the sample surface. By visualizing the distribution of various secondary ions on the sample surface, it is possible to estimate the distribution of the composition and chemical structure on the sample surface.

[0041] By evaluating the surface of sanitary ware using TOF-SIMS under the following measurement conditions, a secondary ion mass spectrum can be obtained, with the horizontal axis representing the mass number (m / z, i.e., the value obtained by dividing the mass m by the charge z) and the vertical axis representing the secondary ion intensity (number of counts). [TOF-SIMS measurement conditions] Primary ion source: Bi 3+ Primary ion acceleration voltage: 30 keV Primary ion current: 0.2 pA (at 10 kHz) Primary ion punching: Yes Measurement range: 500 μm x 500 μm Cycle time: 400 μs Number of pixels: 128 x 128 pixels Vacuum degree: 9 -8 hPa Secondary ions: Negative ions Neutralization gun: Yes

[0042] From the C1s and F1s peaks obtained by XPS, it can be determined whether or not the surface of the sanitary ware 10 contains C—F bonds. If it is determined by XPS that the surface of the sanitary ware contains C—F bonds, then based on this, it is possible to confirm that the surface of the sanitary ware 10 contains perfluoropolyether chains 3 from the secondary ion mass spectrum obtained by TOF-SIMS using the above measurement conditions. Specifically, if there are fragments that appear periodically at equal mass intervals on the high mass side of the m / z of the secondary ion mass spectrum obtained by TOF-SIMS, where the m / z is several hundred or more, then the molecular formula of the repeating unit can be inferred from the mass intervals. A similar inference can be made when there are multiple repeating units. From the presence of C—F bonds obtained by XPS and the degree of agreement of the exact masses and isotopes obtained by TOF-SIMS, it can be determined that the molecular formula of the repeating unit is C x F y O z (x, y, z are integers greater than or equal to 1, where y = 2x) is present, it is clear that the repeating unit contains perfluoroether. Furthermore, the total number of repeating units can be determined from the fragments that appear periodically at equal mass intervals. From the above TOF-SIMS analysis, it is clear that the surface of the sanitary ware 10 contains perfluoropolyether chains 3 when the repeating unit contains perfluoroether and the total number of repeating units is at least 3 or more.

[0043] The perfluoropolyether chain 3 is preferably bonded to the glaze layer via a Si atom. The perfluoropolyether chain 3 is more preferably bonded to the glaze layer via multiple Si atoms. This improves the adhesion between the perfluoropolyether chain 3 and the glaze layer 2. The Si atom is preferably bonded to the end of the perfluoropolyether chain 3. It is more preferable that the Si atom is bonded to the end of the perfluoropolyether chain 3. Although Si atoms may be bonded to both ends of the perfluoropolyether chain 3, it is more preferable that the Si atom is bonded to one end of the perfluoropolyether chain 3. The Si atom bonded to the perfluoropolyether chain 3 may be derived from a reactive silyl group bonded to the perfluoropolyether chain 3 contained in the raw material, or may be an Si atom generated by activating the surface of the glaze layer.

[0044] The hydroxyl group or hydrolyzable group contained in the reactive silyl group preferably functions as a bonding point with the glaze layer 2. In other words, the hydroxyl group contained in the reactive silyl group, or the hydroxyl group obtained by hydrolysis of the hydrolyzable group, or the hydrogen atom contained in the hydroxyl group, undergoes dehydration condensation with a functional group (such as a hydrogen atom or a hydroxyl group) present on the surface of the glaze layer 2. This enables the perfluoropolyether chain 3 to bond to the surface of the glaze layer 2. The perfluoropolyether chain 3 is preferably bonded to the glaze layer 2 via a Si atom. In the present invention, the reactive silyl group preferably contains many hydroxyl groups or hydrolyzable groups. This improves the adhesion between the perfluoropolyether chain 3 and the glaze layer 2.

[0045] The fact that the perfluoropolyether chain 3 is bonded to the glaze layer 2 via a Si atom can be confirmed by, for example, surface-enhanced Raman spectroscopy (SERS), 19 It can be identified by methods such as Si-NMR and infrared spectroscopy (IR).

[0046] The ratio of the number of oxygen atoms to the number of carbon atoms in the perfluoropolyether chain In the present invention, the ratio of the number of oxygen atoms to the number of all carbon atoms having C-F bonds in the perfluoropolyether chain 3 (hereinafter referred to as the "O / C ratio"), obtained by peak separation of a spectrum obtained by measuring the surface of the sanitary ware by X-ray photoelectron spectroscopy (XPS), is 0.1 or more. A higher O / C ratio is preferable because it increases the flexibility of the perfluoropolyether chain 3. Specifically, the O / C ratio is preferably 0.2 or more, more preferably 0.3 or more, and even more preferably 0.4 or more. This gives the perfluoropolyether chain 3 excellent flexibility. The reasons for this are thought to be as follows, but the present invention is not limited thereto. The perfluoropolyether chain 3 contains fluorine atoms, oxygen atoms, and carbon atoms, and it is believed that the fluorine atoms and oxygen atoms are bonded to the carbon atoms. Generally, atoms bonded to carbon atoms are located at the vertices of a regular tetrahedron structure and can freely rotate around the carbon single bond. This allows for countless conformations. When an ether bond is contained in a perfluoropolyether chain, the presence of an oxygen atom between the two carbon atoms bonded to the oxygen atom of the ether bond reduces the interaction between them, and there is almost no difference in energy depending on the twist position. Therefore, organic chains containing ether bonds can rotate relatively freely around the carbon-oxygen single bond. For example, perfluoropolyether chains with many ether bonds have a higher degree of freedom in shape change compared to fluoroalkylsilane compounds that do not contain ether bonds. In other words, they are considered to have excellent flexibility. Furthermore, the excellent flexibility of the perfluoropolyether chain 3 allows the sanitary ware of the present invention to have high durability, particularly abrasion resistance. The method for calculating the O / C ratio will be described later.

[0047] In the present invention, a higher O / C ratio is preferable because the perfluoropolyether chain 3 is considered to have better flexibility when the O / C ratio is high. However, if the flexibility is too high, the perfluoropolyether chain tends to collapse sideways, resulting in a decrease in the height of the perfluoropolyether chain. This increases the probability that water and alkaline components will reach the glaze layer surface from areas where the film has worn away due to the load of repeated use, making it more likely that scale will adhere and film wear will occur. Therefore, the O / C ratio, which is an index of flexibility, is preferably 1.0 or less, more preferably 0.9 or less, and even more preferably 0.8 or less.

[0048] CF relative to the number of all carbon atoms with CF bonds in the perfluoropolyether chain 3 Percentage of carbon atoms with bonds In the present invention, the ratio of the number of carbon atoms having CF3 bonds to the total number of carbon atoms having CF3 bonds in the perfluoropolyether chain 3, obtained by peak separation of a spectrum obtained by measuring the surface of the sanitary ware by X-ray photoelectron spectroscopy (XPS), is 20 at% or less (hereinafter also referred to as "the ratio of the number of carbon atoms having CF3 bonds"). It is believed that by having the ratio of carbon atoms having CF3 bonds be 20 at% or less, excellent flexibility of the perfluoropolyether chain 3 is maintained. In other words, it is believed that when the ratio of carbon atoms having CF3 bonds exceeds 20 at%, the flexibility of the perfluoropolyether chain 3 decreases. The reason for this is that when the ratio of carbon atoms having CF3 bonds exceeds 20 at%, the possibility of containing a perfluoroalkyl chain in the side chain increases. This is thought to easily cause steric hindrance, reducing the degree of rotational freedom of the ether bonds contained in the perfluoropolyether chain, which is the main chain, and thereby reducing flexibility.

[0049] The sanitary ware according to the present invention is believed to have the following effects by including the specific perfluoropolyether chains 3 described above on the surface of the glaze layer having a unique uneven shape.

[0050] The sanitary ware of the present invention has high flexibility in the specific perfluoropolyether chains 3, allowing the perfluoropolyether chains 3 to conform to the unique uneven surface shape of the glaze layer 2. Therefore, even when used under high-stress conditions, the sanitary ware has excellent slide resistance and can maintain stain resistance for a long period of time. Figure 2A shows cross-sectional views of an example of the sanitary ware of the present invention when a load is applied to the surface with a sponge or the like and after the load is applied. When removing stains from the sanitary ware surface, the load applied to the sanitary ware surface by the sponge or the like is thought to be downward and laterally (left and right). The highly flexible surface structure of the sanitary ware 10 of the present invention exhibits a unique effect of dispersing or releasing the load force applied to the bond between the perfluoropolyether chains 3 and the glaze layer 2. This suppresses (reduces) wear on the perfluoropolyether chains 3 and enables the sanitary ware to maintain its slide resistance for a long period of time. In particular, when a force applied laterally is concentrated on the convex portions of the uneven surface, the perfluoropolyether chains 3 can maximize their excellent flexibility. Furthermore, in an embodiment in which the perfluoropolyether chains 3 form a film, flexibility is further enhanced, wear of the film is further suppressed, and the sliding resistance function is maintained for a longer period of time.

[0051] As described above, the sanitary ware of the present invention maximizes its flexibility by including specific perfluoropolyether chains 3 on the surface of the glaze layer 2, which has a unique uneven shape. As a result, the sanitary ware of the present invention can exhibit excellent abrasion resistance.

[0052] In the sanitary ware of the present invention, the specific perfluoropolyether chains 3 described above have high flexibility, allowing the perfluoropolyether chains 3 to conform to the unique uneven shape of the surface of the glaze layer 2. This indicates that the sanitary ware of the present invention not only has excellent slide resistance but also excellent alkali resistance. Normally, even if a certain coating film provided on the surface of the glaze layer itself is alkali-resistant, the glaze layer will dissolve when alkaline components penetrate into the glaze layer, resulting in the entire coating film on the surface of the glaze layer being lost. However, by providing highly flexible perfluoropolyether chains 3 on the surface of the glaze layer, the perfluoropolyether chains 3 can conform to the uneven shape of the glaze layer, improving surface coverage. This makes it possible to prevent alkaline components from penetrating the glaze layer, thereby maintaining alkali resistance for a longer period of time.

[0053] On the other hand, Figure 2B shows a cross-sectional view of sanitary ware containing perfluoropolyether chains in which the proportion of carbon atoms with CF3 bonds exceeds 20 at% and the O / C ratio is less than 0.1, i.e., the chains have low flexibility. As shown in Figure 2B, the perfluoropolyether chains on the surface of the uneven glaze layer cannot withstand force, especially in the lateral direction, and are worn out, presumably preventing the creation of sliding resistance.

[0054] When liquid is present on the inclined surface of the sanitary ware of the present invention, the high flexibility of the specific perfluoropolyether chain 3 improves the ability of the liquid to slide off. This is thought to reduce the amount of liquid remaining on the inclined surface of the sanitary ware. Furthermore, the high flexibility of the specific perfluoropolyether chain 3 makes it easier for liquid present on the surface of the sanitary ware to move to absorbent items such as tissue paper or dishcloths. This is thought to reduce the amount of liquid remaining on the surface of the sanitary ware when it is wiped off with an absorbent item.

[0055] When solids that are insoluble in water or oily organic solvents are present on an inclined surface of the sanitary ware of the present invention, the high flexibility of the specific perfluoropolyether chains 3 improves the ability of the solids to slide off. This is believed to facilitate the sliding of solids present on a sanitary ware surface inclined at an angle of several degrees from the horizontal, even when no external force is applied. Furthermore, even when solids are firmly attached to the sanitary ware surface to the extent that they cannot be removed without mechanical force such as rubbing, the high flexibility of the specific perfluoropolyether chains 3 improves the ability of the solids to slide off. Therefore, it is believed that the solids can be removed with, for example, much less mechanical force than when solids are firmly attached to a sanitary ware surface that does not contain the specific perfluoropolyether chains. In other words, the sanitary ware of the present invention, which contains the specific perfluoropolyether chains 3 on its surface, is believed to enable the removal of solids while applying an efficient mechanical force.

[0056] The ratio of the number of fluorine atoms to the total number of carbon and oxygen atoms in the perfluoropolyether chain In the present invention, the ratio of the number of all fluorine atoms having C-F bonds to the total number of all carbon atoms having C-F bonds and their oxygen atoms in the perfluoropolyether chain 3, as determined by peak separation of a spectrum obtained by measuring the surface of the sanitary ware by X-ray photoelectron spectroscopy (XPS) (hereinafter referred to as the "F / (C+O) ratio"), is preferably 1.1 or more and 1.7 or less. The F / (C+O) ratio is more preferably 1.1 or more and 1.5 or less. This gives the perfluoropolyether chain 3 excellent flexibility and water repellency. The reasons for this are thought to be as follows, but the present invention is not limited thereto. The perfluoropolyether chain contains fluorine atoms, oxygen atoms, and carbon atoms, and the fluorine atoms and oxygen atoms are thought to be bonded to the carbon atoms. Generally, atoms bonded to carbon atoms are located at the vertices of a regular tetrahedron structure, allowing them to freely rotate around the carbon-carbon single bond. This allows for an infinite number of conformations. When a chain contains an ether bond, such as a perfluoropolyether chain, the presence of an oxygen atom between the two carbon atoms bonded to the oxygen atom of the ether bond reduces the interaction between them, resulting in almost no difference in energy depending on the twist position. Therefore, organic chains containing ether bonds can rotate relatively freely around the carbon-oxygen single bond. For example, perfluoropolyether chains with many ether bonds have a higher degree of freedom in shape change compared to fluoroalkyl chains without ether bonds. This suggests that they have excellent flexibility. Furthermore, the greater the proportion of fluorine atoms in the perfluoropolyether chain, the lower the surface energy of the sanitary ware surface. This suggests that they have excellent water repellency. The F / (C+O) ratio indicates the ratio of fluorine atoms to oxygen atoms, assuming a constant number of carbon atoms. Therefore, a higher F / (C+O) ratio indicates a higher proportion of fluorine atoms, i.e., better water repellency. Conversely, a lower F / (C+O) ratio indicates a higher proportion of oxygen atoms, i.e., better flexibility. For example, when the proportion of oxygen atoms present in the perfluoropolyether chain 3 is high, the proportion of fluorine atoms is correspondingly low, resulting in increased flexibility but reduced water repellency.Thus, the water repellency and flexibility of the perfluoropolyether chain are in a trade-off relationship, and it can be said that the balance between water repellency and flexibility is important for producing sanitary ware with high durability and stain resistance. Therefore, the excellent water repellency and flexibility of the perfluoropolyether chain 3 enable the sanitary ware of the present invention to have high stain resistance and long-term durability, especially abrasion resistance. The method for calculating the F / (C+O) ratio will be described later.

[0057] In the present invention, the perfluoropolyether chain 3 is generally preferably one represented by the following formula 7. [ka] Here, p, q, r, and s are the numbers of repeating units, i.e., integers of 0 or more, and the sum of p, q, r, and s is 3 to 200. The repeating units in the formula may be randomly bonded to form a chain, or polymer chains each made of the repeating units may be bonded to each other. f1 and R f2 Each represents an organic chain containing carbon atoms in which hydrogen atoms are substituted with fluorine atoms. The repeating units may be composed of only a straight chain or may include a side chain, but the straight chain is preferred.

[0058] More preferred examples of the perfluoropolyether chain 3 include perfluoropolyether chains represented by the following formulas 8 to 12. [ka] (wherein l:m:n=23.2:22.3:0.4 (average value), and the repeating units in the formula are arranged randomly.) [ka] (wherein the average value of l is 22.9), [ka] (wherein the average value of l is 23.2), [Chemical formula] (where the average value of l is 18.) [Chemical formula] (where the average value of l is 23.4).

[0059] XPS measurement method for the surface of sanitary ware In the present invention, the O / C ratio, the ratio of the number of carbon atoms having a CF3 bond, and the F / (C + O) ratio are obtained by measuring the surface of the sanitary ware by X-ray photoelectron spectroscopy (XPS). Before the XPS measurement, it is preferable to wash the surface of the sanitary ware with a neutral detergent and a sponge, and then thoroughly rinse it with ultrapure water.

[0060] [Obtaining the XPS spectrum] Using a K-ALPHA (manufactured by thermo scientific) as the XPS apparatus, the spectra of C1s, F1s, and O1s can be obtained by performing XPS measurement under the following XPS measurement conditions. When measuring a plurality of samples together, in order to avoid the decomposition of the C—F bond due to X-ray irradiation, it is preferable to perform XPS measurement with each sample separated by at least 1 cm or more. Note that XPS is a method of irradiating soft X-rays onto the sample surface and performing energy analysis by capturing the photoelectrons emitted due to the ionization of the sample surface. Since the obtained spectrum shows the photoelectron peaks emitted from each electron orbit, the obtained photoelectron peaks are expressed by the element symbol and the electron orbit (for example, the photoelectron peak obtained from the 1s orbit of carbon is denoted as "C1s").

[0061] [XPS measurement conditions] X-ray conditions: Monochromatic AlKα ray, 30 W, 12 kV Analysis area: 200 μmφ Neutral gun conditions: 0.1 V, 200 μA Photoelectron extraction angle: 90° Time Per Step: 50 ms Sweep: 5 times Pass energy: 55 eV Analysis element (energy range, step size): C1s (278-308eV, 0.01eV), F1s (679-699eV, 0.03eV), O1s (523-543eV, 0.03eV) Inert gas species: Ar Sputtering voltage: 200V Sputtering area: 2mm x 2mm Sputter cycle: 1 second

[0062] The bond type of the carbon atoms contained in the perfluoropolyether chain 3 (hereinafter referred to as the "carbon atom bond type" or simply "bond type") was identified in the spectrum obtained by XPS measurement of the surface of the sanitary ware. There are five bond types of the carbon atoms contained in the perfluoropolyether chain, (1) to (5), as shown in Table 2 below. Table 2 also lists the C1s bond energies for bond types (1) to (5). The C1s bond energy value for bond type (1) is based on the literature value listed in the NIST Standard Reference Database 20, Version 4.1 (https: / / srdata.nist.gov / xps / ). The C1s bond energy value listed in the database was set up by shifting the C1s bond energy value of a C-C bond to 284.8 eV. Therefore, to match the conditions of this XPS measurement, the C1s bond energy value of organic compounds containing bond type (1) was corrected using the F1s bond energy value contained in that organic compound, 688.5 eV, which is the same as the XPS measurement conditions. For example, bond type (1) is a bond included in the reagent FOMBLIN Y in the NIST database, and the C1s bond energy value is listed as 295.2 eV. Here, the F1s bond energy value of FONBLIN Y is 689.1 eV, so the literature value for this F1s bond energy is corrected to 688.5 eV. In other words, this F1s bond energy value is shifted 0.6 eV toward the lower energy side for correction. Accordingly, the C1s bond energy value is also shifted 0.6 eV toward the lower energy side for correction, resulting in the C1s bond energy value of bond type (1) being 294.6 eV. This value is used as the C1s bond energy value of bond type (1).

[0063] [Table 2]

[0064] In XPS, it is known that the binding energy of the photoelectrons obtained from the target atom (also called the "central atom") varies significantly (i.e., undergoes a chemical shift) depending on the bonding state between the target atom (also called the "central atom") and the atoms surrounding it (also called "adjacent atoms"). Therefore, it is possible to identify which peak corresponds to which bond type in the obtained XPS spectrum from the C1s binding energies of bond types (1) to (5), i.e., peak separation is possible.

[0065] One factor that causes chemical shifts is the difference in electronegativity between neighboring atoms. The more neighboring atoms with high electronegativity there are around a central atom, the more charge imbalance occurs between the central atom (in the present invention, a carbon atom) and the neighboring atoms (in the present invention, fluorine atoms, oxygen atoms, and carbon atoms). As a result, the binding energy of photoelectrons obtained from the central atom (in the present invention, the C1s binding energy) shifts to a higher side. Since the constituent atoms of a perfluoropolyether chain are fluorine atoms, oxygen atoms, and carbon atoms in order of decreasing electronegativity, the more fluorine atoms there are around the central carbon atom, the higher the binding energy of the C1s bond type. Furthermore, the C1s binding energy decreases when the neighboring atoms are oxygen atoms and carbon atoms, respectively. Based on this premise, the bond types (1) to (5) can be arranged in order of decreasing C1s binding energy as follows: (1) > (2) > (3) > (4) > (5). The spectra of bond types (1) to (5) all appear in the C1s binding energy region (289 eV to 298 eV), which is higher than the band of carbon and the like (around 285 eV).

[0066] In the obtained XPS spectrum, we first confirm the influence of the peaks due to potassium on the C1s spectrum. When the base and / or glaze layer for sanitary ware contains potassium, the K2p peak is generally observed in the 296.8±1.0 eV region. 1 / 2 However, depending on the height of the perfluoropolyether chains present on the surface of the glaze layer, even if the sanitary ware base and / or glaze layer contains potassium, a K2p peak may be present in the 296.8±1.0 eV region. 1 / 2In this case, the peak due to potassium may not be observed in the C1s spectrum, and the peak separation described below can be carried out.

[0067] K2p in the 296.8±1.0 eV region of the C1s spectrum 1 / 2 If the peak is confirmed, the following should be considered as the influence of potassium on the C1s spectrum. The peaks derived from potassium that affect the C1s spectrum are K2p 1 / 2 and K2p 3 / 2 Generally, K2p 3 / 2 The peak is K2p 1 / 2 The photoelectron binding energy is 2.8 eV lower than that of K2p 1 / 2 It is twice as large as K2p. 3 / 2 The peak of K2p exists at 294.0±1.0 eV, which overlaps with the peaks derived from the perfluoropolyether chains of bond types (2) and (3) listed in Table 2. 3 / 2 However, it is difficult to confirm the existence of the K2p peak. 1 / 2 The peak of K2p is detected as a single peak in the photoelectron binding energy region, which is separate from the peaks derived from the perfluoropolyether chain. 1 / 2 If the presence of the peak is confirmed, 3 / 2 It is determined that a peak of K2p exists. 1 / 2 From the binding energy and peak area of ​​K2p 3 / 2 It is possible to calculate the binding energy and peak area of ​​the calculated K2p 3 / 2 The peak area of ​​this peak is considered when separating the peaks of the C1s spectrum, and the influence of the peak derived from potassium is removed. Therefore, even when the C1s spectrum is influenced by the peak derived from potassium, it is possible to calculate the composition ratio of each bond type contained in the perfluoropolyether chain.

[0068] <Peak separation> The obtained spectrum is subjected to peak separation using data analysis software Avantage (Version 5, Thermo Scientific). Peak separation involves waveform separation based on detected peaks in the overall waveform of the obtained spectrum, and identifying the bonding state corresponding to each obtained waveform. This peak separation makes it possible to calculate the proportion of different bonding states in the perfluoropolyether chain, even though it is the same element (carbon atom in this invention). The peak separation method is described in detail below. First, in the obtained F1s spectrum, the peak positions are corrected over the entire binding energy range of the measured C1s, F1s, and O1s so that the F1s binding energy of the peak derived from fluorine atoms bonded to carbon atoms is 688.5 eV. In this state, peak separation is performed on the photoelectron spectra of bond types (1) to (5) present in the C1s spectrum. The specific method for C1s peak separation is described below. First, the peak background is removed by the Shirley method within the C1s measurement range from 278 eV (start point) to 300 eV (end point). However, for the start and end points, the average intensity within a ±0.25 eV range with each point as the median is used as the background intensity at that point. For example, at the C1s start point of 278 eV, the average intensity within a ±0.25 eV range of the median 278 eV, i.e., the range of 277.75 eV to 278.25 eV, is used as the background intensity at the start point. Thereafter, the peak at 285 eV in the C1s binding energy is used as a C-C bond or a C-H bond, the peak at 286 eV in the C1s binding energy is used as a C-O bond, the peaks at the C1s binding energy of bond types (1) to (5) listed in Table 2 are used as each bond type, and the peak at 296.8 ±1.0 eV in the C1s binding energy is used as a K2p 1 / 2and add peaks. Other peaks suggested by the software can also be added as necessary. The peak shape of the added peaks must follow a Gauss-Lorentz distribution. Then, fitting is performed using the peak fitting conditions below to obtain spectra for each bond type. If the fitting results do not meet the fitting completion criteria below, a peak is added at the C1s binding energy position that is the maximum among the positive maxima in the second derivative spectrum displayed on the screen, and fitting is performed again using the peak fitting conditions below. This operation is repeated until the fitting completion criteria below are met, and fitting is then completed. Next, K2p in the range of 296.8±1.0 eV is added. 1 / 2 If the peak of K2p is confirmed, remove the influence of the potassium peak by the following procedure. First, 1 / 2 The binding energy, peak height and full width at half maximum (FWHM) of K2p are specified on the software. 3 / 2 The binding energy of K2p 1 / 2 The binding energy of K2p is 2.8 eV smaller than that of 3 / 2 The half width of K2p 1 / 2 Specify the numerical value in the software as being equal to K2p 3 / 2 The peak area of ​​K2p 1 / 2 The peak height is adjusted in the software so that it is 1.95 to 2.05 times the peak area of ​​the original peak. Then, fitting is performed again using the peak fitting conditions below to obtain spectra for each bond type, taking into account the potassium peak. This completes the XPS peak separation. [Peak fitting conditions] Fitting Algorithm:Powell Maximum Iterations: 500 Convergence:1e-05 Gauss-Lorentz Mix:Product [Fitting completion criteria] Normalised Chi Square ≤ 10.0

[0069] <Calculation of the Composition Ratio of the Bond Types of Carbon Atoms Contained in the Perfluoropolyether Chain> From the spectra of the bond types (1) to (5) identified by peak separation of XPS, the composition ratios of the bond types (1) to (5) are calculated using data analysis software Avantage (Version 5, manufactured by Thermo Scientific). The ratio of the peak area intensity of each bond type (1) to (5) to the total peak area intensity (Area Intensity) of the spectra of each bond type (1) to (5) obtained by peak separation is defined as the composition ratio in the perfluoropolyether chain of each bond type (1) to (5), and is calculated in at% units.

[0070] <Calculation of the O / C Ratio> From the composition ratios of the bond types (1) to (5) obtained by peak separation, the O / C ratio contained in the perfluoropolyether chain is obtained. Since the number of carbon atoms and oxygen atoms contained in the perfluoropolyether chain cannot be directly obtained from the calculated composition ratios of the bond types (1) to (5), the O / C ratio is calculated by the following method. Assume that the number of carbon atoms contained in the perfluoropolyether chain is 100, and the composition ratios of the carbon atoms of each of the bond types (1) to (5) are also regarded as the number of carbon atoms as they are. Since the types of atoms bonded to each of the bond types (1) to (5) are fixed, the number of oxygen atoms when the number of carbon atoms in the perfluoropolyether chain is 100 can be obtained. Thereby, the O / C ratio can be obtained.

[0071] For example, as the bond types contained in the perfluoropolyether chain in the compound represented by the above formula (a), (2), (4), and (5) are detected, and the respective composition ratios are 34.0 at%, 56.0 at%, and 10.0 at%, the following conditions: · When C is bonded to the central carbon atom, this C is not counted in the number of carbon atoms · When O is bonded to the central carbon atom, this O is counted as 1 / 2. According to , the number of carbon atoms is a total of 100, which is 34.0 for bond type (2), 56.0 for bond type (4), and 10.0 for bond type (5). Also, the number of oxygen atoms is a total of 62.0, which is 34.0×2×1 / 2 for bond type (2), 56.0×1×1 / 2 for bond type (4), and 10.0×0×1 / 2 for bond type (5). Therefore, the O / C ratio is calculated to be 0.62. By rounding the second decimal place of this calculated O / C ratio, the O / C ratio of the present invention is obtained.

[0072] <Calculation of F / (C + O) ratio> From the composition ratios of bond types (1) to (5) obtained by peak separation, the F / (C + O) ratio contained in the perfluoropolyether chain is obtained. Since the number of carbon atoms, oxygen atoms, and fluorine atoms contained in the perfluoropolyether chain cannot be directly obtained from the calculated composition ratios of bond types (1) to (5), the F / (C + O) ratio is calculated by the following method. Assume that the number of carbon atoms contained in the perfluoropolyether chain is 100, and the composition ratios of the carbon atoms of bond types (1) to (5) are also considered as the number of carbon atoms as they are. Since the types of atoms bonded to each of bond types (1) to (5) are fixed, the number of oxygen atoms and fluorine atoms when the number of carbon atoms in the perfluoropolyether chain is 100 can be obtained. Thereby, the F / (C + O) ratio can be obtained.

[0073] For example, when bond types (2), (4), and (5) are detected as the bond types contained in the perfluoropolyether chain in the compound represented by the above formula (a), and their respective composition ratios are 34.0 at%, 56.0 at%, and 10.0 at%, the following conditions: · When C is bonded to the central carbon atom, this C is not counted in the number of carbon atoms · When O is bonded to the central carbon atom, this O is counted as 1 / 2. · When F is bonded to the central carbon atom, this F is counted as one According to this, the number of carbon atoms is a total of 100, which is 34.0 for bond type (2), 56.0 for bond type (4), and 10.0 for bond type (5). Also, the number of oxygen atoms is a total of 62.0, which is 34.0×2×1 / 2 for bond type (2), 56.0×1×1 / 2 for bond type (4), and 10.0×0×1 / 2 for bond type (5). Further, the number of fluorine atoms is a total of 200.0, which is 34.0×2×1 for bond type (2), 56.0×2×1 for bond type (4), and 10.0×2×1 for bond type (5). Therefore, the F / (C + O) ratio is calculated to be 1.23. By rounding the second decimal place of this calculated F / (C + O) ratio, the F / (C + O) ratio of the present invention is obtained.

[0074] <Calculation of the ratio of the number of carbon atoms having a CF3 bond to the number of carbon atoms having a C - F bond> In the present invention, when the composition ratio of bond type (3) obtained by peak separation is high, that is, exceeds 20 at%, it means that the perfluoropolyether chain has bond type (3). This means that the perfluoropolyether main chain is likely to have a side chain (-CF3).

[0075] Sputtering time measured by XPS depth profile analysis of sanitary ware surfaces In the present invention, in the profile obtained by the depth - direction analysis of XPS described later, starting from the XPS measurement point on the surface of the sanitary ware, the ratio of the absolute value of the difference between the peak area of fluorine atoms (A s ) at a certain measurement point and the peak area of fluorine atoms (A a ) at the previous measurement point and the peak area of fluorine atoms (A b ) at that measurement point with respect to the peak area of fluorine atoms at the starting point is preferably 1.0 at% or less until the end point where the sputtering time is 60 seconds or less. In the present invention, the height of the perfluoropolyether chain 3 contained on the surface of the glaze layer can be specified using the sputtering time by the depth - direction analysis of XPS on the surface of the sanitary ware as an index.

[0076] The sputtering time of the sanitary ware surface can be confirmed by XPS depth profiling using a combination of XPS measurement and Ar ion sputtering. This combination of XPS measurement and Ar ion sputtering is referred to as "XPS depth profiling." For XPS depth profiling, the sanitary ware surface is first cleaned with a neutral detergent, rinsed with ultrapure water, and then blown dry. When measuring multiple samples at once, it is preferable to measure the XPS with each sample spaced at least 1 cm apart to avoid decomposition of C-F bonds due to X-ray irradiation. The sanitary ware surface is then subjected to XPS measurement, followed by alternating between Ar ion sputtering and XPS measurement. The XPS measurement conditions described above can be used. The following conditions can be used for sputtering (hereinafter also referred to as "sputtering conditions"). XPS measurement is performed for each "sputtering cycle" of the sputtering conditions. Spectral information is obtained through XPS depth profiling.

[0077] [Sputtering conditions] Inert gas species: Ar Sputtering voltage: 200V Sputtering area: 2mm x 2mm Sputter cycle: 1 second The sputtering voltage is the voltage applied to the Ar ion gun, the sputtering range is the surface area removed by sputtering, and the sputtering cycle is the time for continuous irradiation of Ar gas for each measurement in the depth direction, with the total sputtering cycle being the sputtering time.

[0078] In the profile obtained by XPS depth direction analysis, the XPS measurement point on the surface of the sanitary ware (i.e., the perfluoropolyether chain) is set as the starting point, and the peak area (A s ) to the peak area of ​​fluorine atoms at a certain measurement point (A a ) and the peak area of ​​fluorine atoms at the previous measurement point (A bThe endpoint is when the absolute value of the difference between the End point: |A b -A a | / A s ≦0.01

[0079] The sputtering time from the start point to the end point can be used as an index of the height of the perfluoropolyether chain.

[0080] In the present invention, the sputtering time from the start point to the end point is preferably within 60 seconds, more preferably within 30 seconds, and even more preferably within 20 seconds. The lower limit of the sputtering time is preferably 5 seconds or more. A suitable range of the sputtering time may be an appropriate combination of the above upper and lower limits.

[0081] The sanitary ware according to the present invention is preferably one in which a large number of perfluoropolyether chains 3 are formed in the form of a film or layer on the surface of the glaze layer 2. The film containing the perfluoropolyether chains 3 is preferably a thin film. When the perfluoropolyether chains 3 are formed in the form of a film or layer, the peak area (A s ) to the peak area of ​​fluorine atoms at a certain measurement point (A a ) and the peak area of ​​fluorine atoms at the previous measurement point (A b The sputtering time until the end point at which the absolute value of the difference between the SiO2 concentration and the SiO2 concentration becomes 1.0 at % or less can be used as an index of the thickness of the film or layer.

[0082] When the perfluoropolyether chain 3 is in the form of a film or layer, its height is preferably 1 nm or more and 10 nm or less, and more preferably 1 nm or more and 5 nm or less.

[0083] The perfluoropolyether chains contained in the surface of the sanitary ware of the present invention may contain two or more types of perfluoropolyether chains, or may contain a single type of perfluoropolyether chain.

[0084] The surface of the sanitary ware of the present invention may contain not only perfluoropolyether chains but also fluoroalkyl chains, but to obtain sufficient durability, the content is preferably low. Specifically, the content of fluoroalkyl chains relative to the total fluorine-based organic chains, such as perfluoropolyether chains and fluoroalkyl chains, contained in the surface of the sanitary ware is preferably less than 50 at %, more preferably 30 at % or less, and even more preferably 10 at % or less. [Example]

[0085] The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

[0086] 1. Preparation of sanitary ware 1-1. Preparation of the base and glaze layer for sanitary ware <Making base materials for sanitary ware> Sanitary ware slip prepared from raw materials such as silica sand, feldspar, limestone, and clay was cast into a plaster mold to obtain a green body. This green body was then dried. The dried green body was then fired in the firing process described below to produce the "sanitary ware base."

[0087] <Preparing the glaze> A number of glaze raw materials were prepared, each having the composition shown in Table 3 below, calculated as oxides. 600 g of each glaze raw material, 400 g of water, and 1 kg of alumina balls were placed in a 2-liter ceramic pot and pulverized in a ball mill for approximately 65 hours to obtain a glaze.

[0088] [Table 3]

[0089] Glaze was spray-coated onto the dried molded body and fired at 1100-1200°C to produce a sanitary ware base material with a glaze layer. The surface of the resulting glaze layer was processed as needed to produce substrates A to F with the arithmetic mean linear roughness Ra shown in Table 4 below. The arithmetic mean linear roughness Ra was measured using a stylus surface roughness measuring device conforming to JIS-B0651 (2001) in accordance with "7. Methods and procedures for evaluation using a stylus surface roughness measuring device" of JIS-B0633 (2001). The color of each glaze layer was primarily due to the pigment. For substrate A, a glaze with the composition shown in Table 3 was applied to a sanitary ware base material, and then a glaze with the composition shown in Table 3, excluding ZrO2 and pigment, was applied and fired to form a glaze layer. Substrate B was obtained by applying a glaze with the composition shown in Table 3 to a sanitary ware base material and firing it to form a glaze layer. Substrate C was obtained by wet blasting Substrate A using non-spherical alumina particles as an abrasive, selecting a particle size range of 1 μm to 100 μm, and appropriately selecting the compressed air supply pressure, projection distance, projection angle, and projection time. Substrate D was obtained by applying a glaze with the composition shown in Table 3, but with an excess of 1 to 10 wt% alkaline earth metal oxide, to a sanitary ware base material and firing it to form a glaze layer. Substrate E was obtained by dry blasting Substrate A using Fuji Random A (manufactured by Fuji Manufacturing Co., Ltd.) abrasive with a particle size of #150 (median particle size 63 to 106 μm) at a compressor pressure of 0.6 MPa and a nozzle diameter of 5 mm. Substrate F was obtained by dry blasting substrate A using Fuji Random A (manufactured by Fuji Manufacturing Co., Ltd.) abrasive with a grain size of #150 (median grain size 63 to 106 μm) under conditions of a compressor pressure of 0.3 MPa and a nozzle diameter of 5 mm.

[0090] [Table 4]

[0091] 1-2.Pretreatment In order to remove dirt present on the surface of the glaze layer and to activate the hydroxyl groups present on the surface, pretreatment 1 or 2 described below was carried out.

[0092] <Pretreatment 1> First, the glaze layer surface was cleaned with a commercially available sponge (i) soaked in a neutral detergent (product name: Clean Ace, manufactured by AS ONE). Next, a small amount of ceria powder (manufactured by Treibacher Industrie AG) was sprinkled on the glaze layer surface, and the glaze layer was washed with a commercially available sponge (ii). Next, the remaining ceria powder was removed with a commercially available sponge (iii) while applying running water to the glaze layer surface, and the glaze layer was further washed with ultrapure water (sponges (i), (ii), and (iii) were different and were used separately). The glaze layer was then immersed in an aqueous solution containing alkaline detergent (product name: Semiclean, manufactured by Yokohama Yushi Kogyo Co., Ltd.) with the concentration adjusted to 5 wt% with ion-exchanged water, and ultrasonically cleaned for 5 minutes. Ultrapure water was then sprayed onto the surface of the glaze layer to remove the alkaline detergent. The glaze layer was then immersed in ultrapure water and ultrasonically cleaned for 5 minutes. Ultrapure water was then sprayed onto the surface of the glaze layer again, and the moisture was removed with an air duster.

[0093] <Pretreatment 2> First, the surface of the glaze layer was washed with a commercially available sponge i soaked in a neutral detergent (product name: Clean Ace, manufactured by AS ONE Co., Ltd.). Next, the surface of the glaze layer was washed with running water to remove the neutral detergent. The glaze layer was then immersed in an aqueous solution containing alkaline detergent (product name: Semiclean, manufactured by Yokohama Yushi Kogyo Co., Ltd.) with the concentration adjusted to 5 wt% with ion-exchanged water, and ultrasonically cleaned for 5 minutes. Ultrapure water was then sprayed onto the surface of the glaze layer to remove the alkaline detergent. The glaze layer was then immersed in ultrapure water and ultrasonically cleaned for 5 minutes. Ultrapure water was then sprayed onto the surface of the glaze layer again, and the moisture was removed with an air duster.

[0094] 1-3. Formation of perfluoropolyether chains <Reagent preparation> The following reagents a to g were prepared, each containing a compound containing a perfluoropolyether chain or a compound containing a fluoroalkyl chain. In all of the reagents a to g, the partial structure containing a carbon atom bonded to fluorine is clearly indicated. In the structural formula of the active ingredient contained in each reagent, X Si means an organic group containing at least one Si atom, but not containing a fluorine atom on the Si atom, bound to a hydroxyl group or a hydrolyzable group. The hydrolyzable group means an alkoxy group or a halogeno group. Specifically, it is -OCH3, -OCH2CH3, or -Cl.

[0095] Reagent a A reagent comprising the following components and containing a compound containing a perfluoropolyether chain represented by formula (a) as an active ingredient: [ka] (wherein l:m:n=23.2:22.3:0.4 (average value), and X Si means an organic group containing an average of 3.0 Si atoms, with no fluorine atoms in the Si atoms, bonded to a hydroxyl group or a hydrolyzable group. The hydrolyzable group means an alkoxy group or a halogeno group. Specifically, it is -OCH3, -OCH2CH3, or -Cl. The repeating units in the formula are arranged randomly. These values ​​were determined by liquid analysis of reagent a using NMR. The number average molecular weight of the perfluoropolyether chain is 19 From the F-NMR results, Si The existence of 1 H-NMR and 29 This was confirmed by the Si-NMR detection spectrum.

[0096] (component) Fluoroalkyl ether (CAS No. 163702-06-4) 30-40% Fluoroalkyl ether (CAS No. 163702-06-5) 40-50% 10-20% of a compound containing a perfluoropolyether chain of formula (a) (active ingredient)

[0097] Reagent B A reagent comprising the following components and containing a compound containing a perfluoropolyether chain represented by formula (b) as an active ingredient: [ka] (wherein the average value of l is 22.9. X Si X in formula (a) except that it contains an average of 2.0 Si atoms Si These values ​​were determined by liquid analysis of reagent b using NMR. The number average molecular weight of the perfluoropolyether chain is 19 From the F-NMR results, Si The existence of 1 H-NMR and 29 This was confirmed by the Si-NMR detection spectrum.

[0098] (component) Ethyl nonafluorobutyl ether (CAS No. 163702-05-4) 25-35% Ethyl nonafluoroisobutyl ether (CAS No. 163702-06-5) 45-55% 15-25% of a compound containing a perfluoropolyether chain of formula (b) (active ingredient)

[0099] Reagent C A reagent comprising the following components and containing a compound containing a perfluoropolyether chain represented by formula (c) as an active ingredient: [ka] (wherein the average value of l is 23.2. X Si X in formula (a) except that it contains an average of 3.7 Si atoms Si These values ​​were determined by liquid analysis of reagent c using NMR. The number average molecular weight of the perfluoropolyether chain is 19 From the F-NMR results, Si The existence of 1 H-NMR and 29 This was confirmed by the Si-NMR detection spectrum.

[0100] (component) Ethyl nonafluorobutyl ether (CAS No. 163702-05-4) 25-35% Ethyl nonafluoroisobutyl ether (CAS No. 163702-06-5) 45-55% 15-25% of a compound containing a perfluoropolyether chain of formula (c) (active ingredient)

[0101] Reagent d A reagent comprising the following components and containing a compound containing a perfluoropolyether chain represented by formula (d) as an active ingredient: [ka] (In the formula, the average value of l is 18, and this value was determined by liquid analysis of the reagent d by NMR. The number average molecular weight of the perfluoropolyether chain is 19 This was confirmed by the results of F-NMR. Si X in formula (a) except that it contains an average of 5.0 Si atoms Si is the same as

[0102] (component) 1,1,1,2,2,3,3,4,4,5,5,6,6-Tridecafluorooctane (CAS No. 80793-17-5) Over 99.5% Less than 0.5% of perfluoropolyether chain-containing silane compound (active ingredient) of formula (d)

[0103] Reagent e A reagent comprising the following components and containing a compound containing a perfluoropolyether chain represented by formula (e) as an active ingredient: [ka] (In the formula, the average value of l is 23.4, and this value was determined by liquid analysis of the reagent e by NMR. The number average molecular weight of the perfluoropolyether chain is 19 This was confirmed by the results of F-NMR. Si X in formula (a) except that it contains an average of 3.0 Si atoms Si is the same as

[0104] (component) Ethyl nonafluorobutyl ether (CAS No. 163702-05-4) 25-35% Ethyl nonafluoroisobutyl ether (CAS No. 163702-06-5) 45-55% 15-25% of a compound containing a perfluoropolyether chain of formula (e) (active ingredient)

[0105] Reagent F A reagent comprising the following components and containing as an active ingredient a compound containing a perfluoropolyether chain (including a CF3 side chain) represented by formula (f): [ka] (In the formula, X Si X in formula (a) except that it contains an average of 1.0 Si atoms Si is the same as

[0106] (component) Fluoroalkyl ether 80-85% 15-20% of a compound (active ingredient) containing a perfluoropolyether chain (including a CF3 side chain) of formula (f)

[0107] Reagent g A reagent containing a compound having a fluoroalkyl chain represented by formula (g) as an active ingredient. [ka] (In the formula, X Si X in formula (a) except that it contains an average of 1.0 Si atoms Si is the same as

[0108] (component) Compounds containing a fluoroalkyl chain of formula (g) (active ingredient, CAS No. 83048-65-1) >98.0%

[0109] <Preparation of processing solution> 206 μL of reagent a was added dropwise to 30 g of fluorine-containing solvent (product name: NOVEC 7200, manufactured by 3M) and gently stirred to obtain treatment solution a, which had a concentration of the active ingredient of reagent a of approximately 0.1 wt%. Treatment solutions b, c, e, f, and g, each containing reagents b, c, e, f, and g, were obtained using a similar method. Because reagent d had a concentration of the active ingredient of 0.1 wt%, it was used as treatment solution d without dilution with a fluorine-containing solvent.

[0110] <Application of processing liquid> Treatment liquid a was applied to the surface of base material A that had been subjected to pretreatment 1 using a spray gun at a pressure of 0.04 MPa, the surface was left to stand for 30 seconds, and then thermally dried in a drying oven at 120°C for 30 minutes. Thereafter, the surface was cured for 3 hours in a thermo-hygrostat chamber set at a temperature of 80°C and a humidity of 80%, and then for 17 hours at room temperature and atmospheric pressure, thereby obtaining the sanitary ware of Example 1. Sanitary ware of Examples 2 to 15 and Comparative Examples 1 to 10 were obtained in the same manner using substrates A to F that had been pretreated as shown in Table 7 below and each treatment liquid.

[0111] 2.Analysis and Evaluation The sanitary wares (Examples 1 to 15 and Comparative Examples 1 to 10) produced as described above were subjected to the following analysis and evaluation.

[0112] 2-1.XPS analysis The surfaces of the sanitary ware of Examples 1 to 5 and Comparative Examples 1 and 2 were measured by X-ray photoelectron spectroscopy (XPS). Prior to the measurement, the surfaces of the sanitary ware were cleaned with a neutral detergent and a sponge, and then thoroughly rinsed with ultrapure water.

[0113] Using a K-ALPHA (made by Thermo Scientific) XPS device, measurements were taken of the surface of each sanitary ware under the following "XPS measurement conditions," and C1s, F1s, and O1s spectra were obtained. Note that if the treatment method using the treatment solution is the same, it is self-evident that the structure of the compound formed will also be the same, and the results of this analysis can be interpreted as showing the structure of the compound itself, regardless of the pretreatment method.

[0114] [XPS measurement conditions] X-ray conditions: monochromatic AlKα radiation, 30W, 12kV Analysis area: 200μmφ Neutralization gun conditions: 0.1V, 200μA Photoelectron take-off angle: 90° Time Per Step: 50 ms Sweep: 5 times Pass energy: 55 eV Analysis element (energy range, step size): C1s (278-308eV, 0.01eV), F1s (679-699eV, 0.03eV), O1s (523-543eV, 0.03eV) Inert gas species: Ar Sputtering voltage: 200V Sputtering area: 2mm x 2mm Sputter cycle: 1 second

[0115] The seven types of bonding states of carbon atoms in the perfluoropolyether chains or fluoroalkyl chains contained in the surfaces of each sanitary ware (hereinafter simply referred to as "bond types") are (1) to (7) as shown in Table 5 below. The C1s bond energies for each of bond types (1) to (7) are shown in Table 5 below. Note that the C1s bond energy values ​​for bond types marked with an * (hereinafter referred to as "bond type *") were corrected as follows to the literature values ​​listed in NIST Standard Reference Database 20, Version 4.1. The C1s bond energy values ​​listed in the database were set up with a shift of 284.8 eV, assuming the C1s bond energy of a C-C bond. Therefore, to match the conditions of this XPS measurement, the C1s bond energy values ​​of organic compounds containing bond type * were corrected using the F1s bond energy value contained in those organic compounds, which is 688.5 eV, the same as the XPS measurement conditions.

[0116] [Table 5]

[0117] <Peak separation> The peaks in the obtained spectrum were separated using data analysis software Avantage (Version 5, Thermo Scientific). First, the peak positions in the obtained F1s spectrum were corrected over the entire binding energy range of the measured C1s, F1s, and O1s so that the F1s binding energy of the peak originating from fluorine atoms bonded to carbon atoms was 688.5 eV. Then, peak separation was performed on the photoelectron spectra of bond types (1) to (7) present in the C1s spectrum. The specific method for C1s peak separation is described below. First, the background of the peak was removed using the Shirley method within the C1s measurement range from 278 eV (start point) to 300 eV (end point). However, for the start and end points, the average intensity within a ±0.25 eV range from the median of each point was used as the background intensity at that point. For example, for the C1s start point of 278 eV, the average intensity within a ±0.25 eV range of 277.75 eV to 278.25 eV from the median of 278 eV was used as the background intensity at the start point. Then, the peak at 285 eV in the C1s binding energy was determined as a C-C bond or a C-H bond, the peak at 286 eV in the C1s binding energy was determined as a C-O bond, the peaks at C1s binding energy of the bond types (1) to (7) listed in Table 5 were determined as each bond type, and the peak at 296.8 ± 1.0 eV in the C1s binding energy was determined as a K2p 1 / 2The peaks were assigned as follows and added. Other peaks suggested by the software were also added as necessary. The added peaks were assumed to have a Gauss-Lorentz distribution in peak shape. Then, fitting was performed using the peak fitting conditions below to obtain spectra for each bond type. If the fitting results did not meet the fitting completion criteria below, a peak was added at the C1s binding energy position that had the maximum positive maximum in the second derivative spectrum displayed on the screen, and fitting was performed again using the peak fitting conditions below. This operation was repeated until the fitting completion criteria below was met, and fitting was completed once. Next, K2p was added in the range of 296.8 ± 1.0 eV. 1 / 2 For the treated solutions a, b, d, e, f, and g in which the peaks were confirmed, the influence of the potassium peak was removed by the following procedure. First, the K2p determined by the above fitting was 1 / 2 The binding energy, peak height and full width at half maximum (FWHM) of K2p were specified on the software. 3 / 2 The binding energy of K2p 1 / 2 The binding energy of K2p is 2.8 eV smaller than that of 3 / 2 The half width of K2p 1 / 2 The software specified the value as equal to K2p 3 / 2 The peak area of ​​K2p 1 / 2 The peak height was adjusted in the software so that it was 1.95 to 2.05 times the peak area of ​​the original peak. Then, fitting was performed again using the following peak fitting conditions to obtain spectra for each bond type, taking into account the potassium peak. This completes the XPS peak separation. [Peak fitting conditions] Fitting Algorithm:Powell Maximum Iterations: 500 Convergence:1e-05 Gauss-Lorentz Mix:Product [Fitting completion criteria] Normalised Chi Square ≤ 10.0

[0118] The XPS spectra of the surfaces of each sanitary ware and the results of peak separation are shown in Figs. 3 to 9.

[0119] <Calculation of the composition ratio of the bonding types of carbon atoms contained in the perfluoropolyether chain or fluoroalkyl chain> From the spectra of the bonding types (1) to (7) identified by peak separation, the composition ratios of the bonding types (1) to (7) were calculated using data analysis software Avantage (Version 5, manufactured by Thermo Scientific). Specifically, the ratio of the peak area intensity of the spectra of each bonding type (1) to (7) to the total peak area intensity of all the spectra of the bonding types (1) to (7) obtained by XPS measurement and peak separation was defined as the composition ratio in the perfluoropolyether chain or fluoroalkyl chain of each bonding type (1) to (7), and calculated in at% units. The results are shown in Table 6.

[0120]

Table 6

[0121] < CF relative to the number of carbon atoms with C-F bonds 3 Calculating the percentage of carbon atoms with bonds ><U The composition ratio of the bonding type (3) in the perfluoropolyether chain was calculated. The obtained results are shown in Table 7 below.

[0122] s <Calculation of the O / C ratio> From the composition ratios of the bonding types (1) to (7) obtained by peak separation, the O / C ratio of the perfluoropolyether chain or fluoroalkyl chain was calculated using the method already described. The results are shown in Table 7 below.

[0123] <Calculation of the F / (C + O) ratio> From the composition ratios of the bond types (1) to (7) obtained by peak separation, the F / (C+O) ratio of the perfluoropolyether chain or the fluoroalkyl chain was calculated using the method already described. The results are shown in Table 7 below.

[0124] 2-2. Confirmation of sputtering time by XPS depth direction analysis of the surface of sanitary ware An XPS depth direction analysis was carried out on the surface of the sanitary ware. After XPS measurement of the sanitary ware surface, sputtering using Ar ions and XPS measurement were alternately repeated using the aforementioned "XPS measurement conditions" and "sputtering conditions." XPS measurement was carried out for each "sputtering cycle" of the sputtering conditions. Spectral information was obtained through XPS depth direction analysis. The XPS measurement point on the surface of each sanitary ware was set as the starting point, and the peak area (A s ) to the peak area of ​​fluorine atoms at a certain measurement point (A a ) and the peak area of ​​fluorine atoms at the previous measurement point (A b The point at which the absolute value of the difference between the starting point and the end point became 1.0 at % or less was taken as the end point, and the sputtering time from the starting point to the end point was calculated. The results are shown in Table 7.

[0125] 2-3. Evaluation of water stain removal performance Each sanitary ware was subjected to the following durability test 1 or durability test 2, and then an evaluation of its ability to remove limescale was carried out.

[0126] Durability test 1: Sliding test 1 to 2 mL of ion-exchanged water was dropped onto the surface of the sanitary ware, and the nonwoven fabric part of the sponge (Scotch-Brite (registered trademark) hybrid bonded sponge, manufactured by 3M Japan) was subjected to a load of 50 g / cm. 2 The sponge was pressed against the surface and then moved back and forth 20,000 times.

[0127] Durability test 2: Sliding test after alkali immersion Each piece of sanitary ware was immersed in an alkaline cleaning agent (Kabikira, manufactured by Johnson & Johnson) maintained at 40°C for 16 hours. After that, the sanitary ware was removed and rinsed with running water, then with ultrapure water, and the moisture was removed with an air duster. Next, the above-mentioned durability test 1 (sliding test) was conducted.

[0128] Durability test 3: Sliding test after alkali immersion Each piece of sanitary ware was immersed in an alkaline cleaner (Kabikira, manufactured by Johnson & Johnson) maintained at 25°C for 1.6 hours. After that, each piece was removed and rinsed with running water, then with ultrapure water, and the moisture was removed with an air duster. Next, 1 to 2 mL of ion-exchanged water was dropped onto the surface of each piece of sanitary ware, and the nonwoven fabric part of a sponge (Scotch-Brite (registered trademark) hybrid laminated sponge, manufactured by 3M Japan) was immersed under a load of 50 g / cm. 2 The sponge was pressed against the surface and then moved back and forth 6,000 times.

[0129] Water stain removal evaluation Test water was prepared by diluting commercially available water containing 9.0-10.0 mg of silica (Si), 1.0-2.0 mg each of sodium (Na), calcium (Ca), and magnesium (Mg), and 0-1.0 mg of potassium per 100 mL of water, 5.5 times with ion-exchanged water. 200 μL of this test water was dropped onto the surface of the sanitary ware after durability test 1, durability test 2, or durability test 3, and then dried for 16 hours in a constant temperature and humidity chamber set at 25°C and 70% humidity under atmospheric pressure, allowing limescale to form on the surface.

[0130] A bathroom sponge (Scotch-Brite (registered trademark) Bath Shine Antibacterial Sponge (with special abrasive particles), manufactured by 3M Japan) was soaked in ion-exchanged water, and then a single push (approximately 1 mL) of bathroom detergent (Magiclean Bath Foaming Spray, manufactured by Kao) was sprayed onto the surface of the sponge to create a foam. The sponge surface was then subjected to a load of 200 g / cm on the surface of a sanitary ware surface on which limescale had formed. 2 The sample was pressed against the plate and slid back and forth five times.

[0131] After the sliding, it was visually confirmed whether the limescale on the surface of the sanitary ware had been completely removed. If it had been completely removed, it was judged as ○, and if even a small amount of limescale remained, it was judged as ×. The results are shown in Table 7 below.

[0132] [Table 7] [Explanation of symbols]

[0133] 1. Base for sanitary ware 2 Glaze layer 3 Perfluoropolyether chain 10 Sanitary ware

Claims

1. A sanitary ware comprising a base for sanitary ware and a glaze layer provided on the surface of the base, The glaze layer has an arithmetic mean linear roughness Ra of its surface of 0.03 μm or more and 2.5 μm or less, The surface of the sanitary ware is formed of a perfluoropolyether chain represented by the following formula 7: 【Chemical 1】 (In the formula, p, q, r, and s are the numbers of repeating units, i.e., integers of 0 or more, and the sum of p, q, r, and s is 3 to 200. The repeating units in the formula may be bonded randomly, or the polymer chains made of the repeating units may be bonded to each other. R ｆ１ and R ｆ２ represents an organic chain containing carbon atoms in which hydrogen atoms have been replaced by fluorine atoms.) Including, the perfluoropolyether chains form a film, the ratio of the number of oxygen atoms to the number of all carbon atoms having C—F bonds on the surface of the sanitary ware, which is obtained by peak separation of a spectrum obtained by measuring the surface of the sanitary ware by X-ray photoelectron spectroscopy (XPS), is 0.1 or more and 1.0 or less; The C—F ratio of the number of all carbon atoms having C—F bonds on the surface of the sanitary ware obtained by the peak separation is ３ The ratio of the number of carbon atoms having bonds is 20 at % or less, In the profile obtained by the XPS depth direction analysis, the XPS measurement point on the surface of the sanitary ware is set as the starting point, and the peak area (A ｓ ) to the peak area (A) of fluorine atoms at a certain measurement point ａ ) and the peak area of ​​fluorine atoms at the measurement point immediately before that point (A ｂ the sputtering time until the end point at which the ratio of the absolute value of the difference between the The XPS depth direction analysis was performed under the following XPS measurement conditions: X-ray conditions: monochromatic AlKα radiation, 30 W, 12 kV Analysis area: 200μmφ Neutralization gun conditions: 0.1 V, 200 μA Photoelectron take-off angle: 90° Time Per Step: 50ms Sweep: 5 times Pass energy: 55eV Analyzed elements (energy range, step size): C1s (278-308 eV, 0.01 eV), F1s (679-699 eV, 0.03 eV), O1s (523-543 eV, 0.03 eV) and sputtering under the following conditions: Inert gas species: Ar Sputtering voltage: 200 V Sputtering area: 2 mm x 2 mm Sputter cycle: 1 second The sanitary ware is characterized in that the method is carried out in combination with sputtering at 2000.

2. The perfluoropolyether chain represented by the formula 7 is a perfluoropolyether chain represented by the following formulas 8 to 12: 【Chemistry 2】 (wherein l:m:n=23.2:22.3:0.4 (average value), and the repeating units in the formula are arranged randomly); 【Chemistry 3】 (wherein the average value of l is 22.9); 【Chemistry 4】 (wherein the average value of l is 23.2); 【Chemistry 5】 (wherein the average value of l is 18); 【Chemistry 6】 (wherein the average value of l is 23.4.) The sanitary ware according to claim 1, comprising at least one selected from the group consisting of:

3. 3. The sanitary ware according to claim 1, wherein the glaze layer has a surface with an arithmetic mean linear roughness Ra of 0.03 μm or more and 1.5 μm or less.

4. 4. The sanitary ware according to claim 3, wherein the glaze layer has a surface with an arithmetic mean linear roughness Ra of 0.03 μm or more and 1.0 μm or less.

5. 5. The sanitary ware according to claim 1, wherein the ratio of the number of oxygen atoms to the number of all carbon atoms having C—F bonds on the surface of the sanitary ware, obtained by the peak separation, is 0.2 or more and 1.0 or less.

6. 6. The sanitary ware according to claim 5, wherein the ratio of the number of oxygen atoms to the number of all carbon atoms having C—F bonds on the surface of the sanitary ware, obtained by the peak separation, is 0.4 or more and 1.0 or less.

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