Yellow overglaze color fluorescent pigment as well as preparation method and application thereof

Abstract

The invention provides a yellow overglaze color fluorescent pigment as well as a preparation method and application thereof, and belongs to the technical field of inorganic pigments. The yellow overglaze color fluorescent pigment provided by the invention comprises a fluorescent pink color base, a flux, glass fibers, methyl cellulose and a polymer binder. The fluorescent powder is adopted as a color base to prepare the novel overglaze color fluorescent pigment, the fluorescent pigment can show more dazzling colors by emitting visible light under effective excitation, and the fluorescent pigment can be stably sintered on the surface of porcelain while the color performance and the luminescence performance of the porcelain are ensured. The yellow overglaze color fluorescent pigment provided by the invention is pure in color, moderate in viscosity and capable of being effectively attached to a porcelain glaze surface, a colored pattern is bright and beautiful, the surface is smooth, and meanwhile, the fired pattern after colored drawing can emit bright yellow light under the excitation of near ultraviolet light and blue light, so that the ornamental value of a ceramic product is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of inorganic pigments, and particularly to a yellow overglaze fluorescent pigment, a preparation method thereof, and an application thereof. Background Art

[0002] Overglaze color is a very important technology for modifying the surface of porcelain products. Compared with underglaze color and in-glaze color, overglaze color has its unique expressive ability and is widely used in the field of porcelain art processing. Generally speaking, overglaze color pigments are composed of a color base and a flux. The color base provides basic color support, while the flux ensures that the pigment can be sintered onto the surface of the porcelain at a low temperature to form an overglaze color coating. Among them, the performance of the color base is crucial for the pigment, and its color rendering ability determines the color performance of the pigment.

[0003] At present, the main component of the color base of yellow overglaze color pigments is inorganic mineral pigments, such as chrome yellow, strontium yellow, etc. The excellent colors they exhibit allow painters to draw various artistic creations on the surface of porcelain. However, traditional inorganic mineral pigments still rely on reflecting visible light to show colors (such as golden yellow), and their manifestation forms are relatively single and the colors are monotonous. Summary of the Invention

[0004] The purpose of the present invention is to provide a yellow overglaze fluorescent pigment, a preparation method thereof, and an application thereof, to improve problems such as the monotonous yellow color of overglaze color pigments in the prior art and to fill the gap in overglaze fluorescent pigments in the prior art.

[0005] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions: The present invention provides a yellow overglaze fluorescent pigment, comprising the following raw materials for preparation in parts by mass: 20-40 parts of a fluorescent pink color base, 60-80 parts of a flux, 1-5 parts of a polymer binder, 1-5 parts of glass fiber, and 1-5 parts of methyl cellulose; The fluorescent pink color base is YAG:Ce,Gd fluorescent powder.

[0006] Preferably, it comprises the following raw materials for preparation in parts by mass: 30 parts of a fluorescent pink color base, 70 parts of a flux, 2 parts of a polymer binder, 2 parts of glass fiber, and 3 parts of methyl cellulose.

[0007] Preferably, the polymer binder comprises polyacrylic acid resin or epoxy resin.

[0008] The present invention provides a preparation method of the yellow overglaze fluorescent pigment as described in the above technical solution, comprising the following steps: Mix and grind the fluorescent pink color base and the flux with absolute ethanol and then dry to obtain a powder material; Mix the powder material with glass fiber, polymer binder and methyl cellulose to obtain a mixed material; Grind and dry the mixed material in sequence to obtain the yellow overglaze fluorescent pigment.

[0009] Preferably, grind until the fineness of the material ≤ 15 μm.

[0010] Preferably, the drying temperature of the mixed material is 60 - 80 °C and the time is 0.5 - 1 h.

[0011] The present invention provides the application of the yellow overglaze fluorescent pigment described in the above technical solution or the yellow overglaze fluorescent pigment prepared by the preparation method described in the above technical solution in overglaze porcelain.

[0012] The present invention provides a yellow overglaze fluorescent pigment, and the preparation raw materials include fluorescent pink base, flux, glass fiber, methyl cellulose and polymer binder. The present invention uses yellow fluorescent powder as the color base to formulate a new overglaze fluorescent pigment. This fluorescent pigment can show a more dazzling fluorescent yellow color by emitting visible light under effective excitation, and can be stably sintered on the porcelain surface while ensuring its color performance and luminescence performance. Compared with traditional pigments that can only reflect light, the advantage of the present invention lies in the superposition of reflected light and self-luminescence of the powder. The fluorescent pigment can absorb near-ultraviolet and blue light in sunlight and emit corresponding fluorescence, thus presenting a brighter fluorescent color.

[0013] The yellow overglaze fluorescent pigment provided by the present invention not only has pure color and moderate viscosity, can effectively adhere to the porcelain glaze surface, but also has bright and beautiful painted patterns and a smooth surface. At the same time, the patterns fired after painting can emit bright yellow light under the excitation of near-ultraviolet light and blue light, thus greatly improving the ornamental value of ceramic products.

[0014] The fluorescent pink base used in the present invention is environmentally friendly, pollution-free, safe and reliable. The use of fluorescent powder fundamentally solves the possibility of lead and cadmium dissolution in overglaze colors, is environmentally friendly and non-toxic, and has a wide range of application fields. Description of the Drawings

[0015] Figure 1 It is the reflection spectrogram of the yellow overglaze fluorescent pigment in Example 2 and the commercially available pigment in Comparative Example 1; Figure 2 It is the pictures of the yellow overglaze fluorescent pigment in Example 2 before and after being irradiated by a purple light lamp after being sintered onto a porcelain chip; Figure 3 It is the excitation and emission spectra of the yellow overglaze fluorescent pigment in Example 2 after being sintered onto a porcelain chip; Figure 4 It is the comparison photos of the yellow overglaze fluorescent pigment in Examples 1 - 3 after being sintered onto a porcelain chip; Figure 5 It is a comparison photo of the yellow overglaze fluorescent pigment in Example 2 and the commercially available pigment in Comparative Example 1 after sintering on a porcelain chip. Detailed implementation manners

[0016] In the present invention, unless otherwise specified, the raw materials or reagents required for preparation are all commercially available products well-known to those skilled in the art.

[0017] The present invention provides a yellow overglaze fluorescent pigment, which comprises the following raw materials for preparation in parts by mass: 20 - 40 parts of a fluorescent pink base, 60 - 80 parts of a flux, 1 - 5 parts of a polymer binder, 1 - 5 parts of glass fiber, and 1 - 5 parts of methyl cellulose; The fluorescent pink base is YAG:Ce,Gd phosphor.

[0018] In the present invention, the mass fraction of the fluorescent pink base is 20 - 40 parts, more preferably 25 - 30 parts; the mass fraction of the flux is 60 - 80 parts, preferably 70 - 75 parts; the mass fraction of the polymer binder is more preferably 2 - 3 parts; the mass fraction of the glass fiber is more preferably 2 - 3 parts; the mass fraction of the methyl cellulose is more preferably 2 - 3 parts.

[0019] In the present invention, the composition of the YAG:Ce,Gd phosphor is yttrium aluminum garnet Y 3 Al 5 O 12 doped with Ce and Gd. This fluorescent pink base is excited by blue light to emit yellow light, presenting orange - yellow. The YAG:Ce,Gd phosphor is a commercially available product. The YAG:Ce,Gd phosphor used in the present invention can still maintain its performance without decomposition phase change at the overglaze sintering temperature.

[0020] The present invention has no special limitation on the flux, and commercially available fluxes for overglaze well - known in the art can be used.

[0021] In the present invention, glass fiber can improve the crack resistance and wear resistance of the pigment coating, and reduce the cracks caused by glaze layer shrinkage during high - temperature firing; methyl cellulose can provide temporary adhesion during the painting process, so that the pigment powder firmly adheres to the glaze surface before drying.

[0022] The present invention has no special limitation on the specifications of the glass fiber and methyl cellulose, and commercially available products well - known in the art can be used.

[0023] In the present invention, the polymer binder preferably comprises a polyacrylic resin or an epoxy resin. The present invention has no special limitation on the specific specifications of the polyacrylic resin and the epoxy resin, and commercially available products well-known in the art can be used. In the present invention, the polymer binder can form a continuous transparent organic film layer during the pigment painting process, enhance the adhesion between the pigment and the glaze surface, and at the same time endow the coating with flexibility and reduce microcracks before firing.

[0024] As a preferred embodiment of the present invention, the yellow overglaze fluorescent pigment comprises the following raw materials in parts by mass for preparation: 30 parts of fluorescent pink base, 70 parts of flux, 2 parts of polymer binder, 2 parts of glass fiber, and 3 parts of methyl cellulose.

[0025] The present invention provides a method for preparing the yellow overglaze fluorescent pigment described in the above technical solution, comprising the following steps: Mix and grind the fluorescent pink base and the flux with absolute ethanol and then dry to obtain a powder material; Mix the powder material with glass fiber, polymer binder, and methyl cellulose to obtain a mixture; Grind and dry the mixture in sequence to obtain the yellow overglaze fluorescent pigment.

[0026] The present invention has no special limitation on the dosage of absolute ethanol and the processes of mixing, grinding, and drying. The materials can be mixed evenly according to the processes well-known in the art and dried under well-known conditions.

[0027] The present invention preferably adds glass fiber, polymer binder, and methyl cellulose to the powder material, stirs evenly to obtain a mixture, places it in a mortar for grinding and then dries to obtain the yellow overglaze fluorescent pigment.

[0028] In the present invention, the grinding is carried out until the fineness of the material ≤ 15 μm.

[0029] In the present invention, the drying temperature of the mixture is preferably 60 - 80 °C, more preferably 80 °C, and the time is preferably 0.5 - 1 h, more preferably 1 h.

[0030] The present invention provides the application of the yellow overglaze fluorescent pigment described in the above technical solution or the yellow overglaze fluorescent pigment prepared by the preparation method described in the above technical solution in overglaze porcelain. The present invention has no special limitation on the application method, and it can be used according to the method of traditional overglaze pigments, that is, painting and color firing after oil adjustment.

[0031] The following is a detailed description of the specific embodiments of the present invention. It should be understood that the protection scope of the present invention is not limited by the specific embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the protection scope of the present invention. The experimental methods described in the embodiments of the present invention are all conventional methods unless otherwise specified.

[0032] The following experimental methods and detection methods are all conventional methods unless otherwise specified; the following reagents and raw materials are all commercially available unless otherwise specified.

[0033] In the following examples, the sources of each raw material are as follows: YAG:Ce,Gd phosphor: Jiangmen Keheng Industry Co., Ltd.; Flux: Taiyuan Hengtai Mineral Materials Co., Ltd., with a melting point of 600 - 800 °C; Polyacrylic acid resin: Shanghai Macklin Biochemical Co., Ltd., 400 mPa·s; Glass fiber: Shanghai Macklin Biochemical Co., Ltd., F832297; Methyl cellulose: Shanghai Macklin Biochemical Co., Ltd., L100.

[0034] Example 1

[0035] Weigh 20 parts of YAG:Ce,Gd phosphor, 80 parts of flux, 2 parts of polyacrylic acid resin, 2 parts of glass fiber, and 3 parts of methyl cellulose by weight; Mix the weighed YAG:Ce,Gd phosphor with the flux and absolute ethanol, then grind and dry at 80 °C for 1 h to obtain a powder. Add the weighed polyacrylic acid resin, glass fiber, and methyl cellulose to the above powder, stir evenly, and then grind the obtained mixture in a mortar until the fineness of the material is ≤ 15 μm, and dry at 80 °C for 1 h to obtain a yellow overglaze fluorescent pigment.

[0036] Example 2

[0037] Weigh 30 parts of YAG:Ce,Gd phosphor, 70 parts of flux, 2 parts of polyacrylic acid resin, 2 parts of glass fiber, and 3 parts of methyl cellulose by weight; The preparation method is the same as that of Example 1.

[0038] Example 3

[0039] Weigh 40 parts of YAG:Ce,Gd phosphor, 60 parts of flux, 2 parts of polyacrylic acid resin, 2 parts of glass fiber, and 3 parts of methyl cellulose by weight; The preparation method is the same as that of Example 1.

[0040] Comparative Example 1 The commercially available pigment (thin yellow mineral pigment produced by Jingdezhen Zhongqi Ceramic Culture Co., Ltd.) was used as Comparative Example 1.

[0041] Performance Test The porcelain chips painted with the yellow overglaze fluorescent pigments prepared in Examples 1 to 3 and the commercially available pigment in Comparative Example 1 were placed in an air box furnace. In an air atmosphere, the temperature was programmed to rise from room temperature to 760 °C within 4 h and then the program was stopped and the furnace was cooled with the samples. The pigments were sintered onto the porcelain chips. A bench-top colorimeter was used to test the samples. The samples were directly measured using ultraviolet and visible light as the light source and the reflection mode. The comparative measurement mode was used to compare the magnitude of the parameter values of different samples, so as to determine the positive effect of the chromophore content on the overglaze fluorescent pigment. The specific results are shown in Table 1.

[0042] Table 1 Test data of chromaticity values of the yellow overglaze fluorescent pigments in Examples 1 to 3 and the commercially available pigment in Comparative Example 1 after sintering onto porcelain chips

[0043] As can be seen from Table 1, the content of the fluorescent pink chromophore has a relatively obvious effect on the yellowness value b* of the fluorescent pigment. This may be because too much or too little chromophore will cause the powder to be unable to spread evenly, thus affecting the color rendering ability. The yellowness value of the fluorescent pigment in Example 3 is the best, and the brightness value L* basically remains unchanged. The fluorescent pigments in Examples 1 to 3 exhibit the same yellow color rendering ability as the commercially available pigment in Comparative Example 1. At the same time, due to the excellent luminescent properties of the fluorescent powder, the brightness value L* parameter has been significantly improved, indicating that the fluorescent pigment can achieve a higher lightness performance while maintaining the color purity. The decrease in the redness value a* further optimizes the color performance, making it present a more vivid and bright fluorescent yellow tone.

[0044] Figure 1 Fig. 17 is the reflection spectrum diagram of the yellow overglaze fluorescent pigment in Example 2 and the commercially available pigment in Comparative Example 1. It can be seen that the fluorescent pigment has a stronger reflection in the yellow light range around 550 nm. The reflectance of the fluorescent pigment in Example 2 in the yellow light region of 550 - 600 nm is more prominent, and the reflection intensity is 23% higher than that of the commercially available pigment, indicating that the strong yellow light emission of the fluorescent pigment plays an additive role in the yellow light reflection of the body color.

[0045] Figure 2 Fig. 21 are the pictures of the yellow overglaze fluorescent pigment in Example 2 sintered onto a porcelain chip before and after being irradiated with an ultraviolet lamp (ZF-1 three-purpose ultraviolet analyzer of Hangzhou Qiwei Instrument Co., Ltd., 365 nm near-ultraviolet light). It can be seen that the fluorescent pigment shows a more dazzling color when irradiated.

[0046] Figure 3It is the excitation and emission spectra of the yellow overglaze fluorescent pigment sintered onto the porcelain piece in Example 2. It can be seen that this fluorescent pigment still emits yellow light at about 578 nm when excited at about 460 nm.

[0047] Figure 4 It is the comparison photos of the yellow overglaze fluorescent pigments sintered onto the porcelain piece in Examples 1 to 3. It can be seen that in Example 1, there is too much flux inside the overglaze coating, and in Example 3, there is a phenomenon of color base accumulation, both showing poor colors. While in Example 2, the color base and the flux can be evenly mixed, making the color of the overglaze very uniform.

[0048] Figure 5 It is the comparison photos of the yellow overglaze fluorescent pigment in Example 2 and the commercially available pigment in Comparative Example 1 sintered onto the porcelain piece. The color coordinates of the commercially available pigment calculated on the CIE 1931 xy software for the two comparison photos are (CIEX, CIEY) = (0.4331, 0.4452), and the color coordinates of the fluorescent pigment are (CIEX, CIEY) = (0.4157, 0.4365). Comparing the coordinate values of the commercially available pigment and the fluorescent pigment, it can be seen that the color coordinates of the fluorescent pigment in Example 2 are moving in a brighter direction (the color coordinates of white are 0.3127, 0.3290). And according to Figure 5 it can be known that in terms of visual perception, the fluorescent pigment presents a brighter and more vivid lemon yellow, while the commercially available pigment is darker yellow.

[0049] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A yellow overglaze fluorescent pigment, characterized in that: The preparation comprises the following raw materials in parts by weight: 20-40 parts of fluorescent pink base, 60-80 parts of flux, 1-5 parts of polymer binder, 1-5 parts of glass fiber, 1-5 parts of methyl cellulose; The fluorescent pink base is YAG:Ce,Gd fluorescent powder.

2. The yellow overglaze fluorescent pigment according to claim 1, characterized in that: The preparation comprises the following raw materials in parts by weight: 30 parts of fluorescent pink base, 70 parts of flux, 2 parts of polymer binder, 2 parts of glass fiber, and 3 parts of methyl cellulose.

3. The yellow overglaze fluorescent pigment according to claim 1 or 2, characterized in that: The polymer binder includes polyacrylic resin or epoxy resin.

4. The method for preparing the yellow overglaze fluorescent pigment according to any one of claims 1 to 3, characterized in that: The following steps are involved: The fluorescent pink base and the flux are mixed with anhydrous ethanol, ground and dried to obtain a powder; mixing the powder with glass fiber, a polymer binder and methyl cellulose to obtain a mixture; The mixed material is ground and dried in sequence to obtain a yellow overglaze fluorescent pigment.

5. The preparation method according to claim 4, characterized in that: The grinding is performed until the fineness of the material is ≤15 μm.

6. The preparation method according to claim 4, characterized in that: The mixture is dried at a temperature of 60-80° C. for a time of 0.5-1 h.

7. Use of the yellow overglaze fluorescent pigment according to any one of claims 1 to 3 or the yellow overglaze fluorescent pigment prepared by the preparation method according to any one of claims 4 to 6 in overglaze colored porcelain.

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