JP2014159618A - Surface treatment agent for silver or silver alloy, light-reflecting substrate, light emitting device and method of producing light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface treatment agent having excellent discoloration (corrosion) prevention properties for various kinds of silver or silver alloys, for example, silver or silver alloys used for an electronic component and a lighting device such as a light-emitting diode and, particularly, capable of imparting excellent discoloration resistance to a silver plated surface.SOLUTION: A surface treatment agent for silver or silver alloys comprises liquid A comprising a cationic electrolyte polymer, and liquid B comprising a laminar silicate compound.

Description

  The present invention relates to various silver or silver alloy surface treatment agents, and more particularly to a surface treatment agent for preventing discoloration of silver or silver alloys used in electronic parts, light emitting devices and the like. The present invention also relates to a light reflecting substrate, a light emitting device, and a method for manufacturing the light emitting device.

  Silver or a silver alloy has been used as a noble metal as a decorative article, money, tableware, electronic material, lighting device, dental material, etc. for a long time using its excellent optical properties and electrochemical properties. Particularly recently, the demand as a reflective material for light emitting diodes has been rapidly increasing. The demand for light-emitting diodes is also rapidly increasing in applications such as lighting equipment for automobiles and fluorescent lamps or incandescent lamps.

  However, silver or silver alloys used for these applications are chemically very unstable and easily react with oxygen, moisture, hydrogen sulfide, sulfurous acid gas, etc. in the air to produce silver oxide or silver sulfide. , Thereby having the disadvantage that the silver surface is discolored (corroded) to brown or black. If silver or a silver alloy changes color, the function as a reflective material will fall.

  As a method for preventing discoloration of silver or a silver alloy, for example, in Patent Document 1 below, in a silver coating composition containing a silicon acrylic resin component as a coating film base component, carboxylic acid as a silver deactivating component is used. A composition for silver coating composition comprising 0.01 to 5% by weight of a zirconium complex in a coating film resin is disclosed. Patent Document 2 below proposes a surface treatment agent for silver and a silver alloy containing a specific imidazole compound. Patent Document 3 below discloses an addition-curable silicone resin composition containing specific organosilicon compounds, organohydrogenpolysiloxanes, and platinum-based catalysts as essential components. An optical semiconductor device including an optical semiconductor element sealed with a cured product is also shown.

JP-A-10-158572 JP 2004-238658 A JP 2010-248413 A

  However, the treatment agents of Patent Documents 1 and 2 have the disadvantage that they have low resistance to ultraviolet rays and change color due to long-term exposure to ultraviolet rays. Since light emitting diodes used in lighting equipment and automotive applications use near-ultraviolet light, it is difficult to maintain the light emission intensity even when the treatment agent is applied to the light reflecting layer of a light emitting device including the light emitting diodes. It is. Moreover, in addition to the insufficient malleability of the sealing resin of Patent Document 3, when it is used as a sealing material for a light emitting diode, stress may be generated due to heat generated during driving, and the adhesive resin may be peeled off. is there. As a result, the gas shielding property is lowered, so that discoloration of silver or a silver alloy used as the light reflecting layer cannot be sufficiently suppressed.

  The objective of this invention is providing the surface treating agent of silver or a silver alloy which can provide the outstanding discoloration resistance to the surface of silver or a silver alloy. Another object of the present invention is to provide a light-reflecting substrate excellent in discoloration resistance and a light-emitting device in which the light emission intensity is unlikely to decrease, provided with a treatment layer free from cracks and cracks formed from the surface treatment agent. It is.

  The present invention provides a surface treatment agent for silver or a silver alloy, which comprises a liquid A containing a cationic electrolyte polymer and a liquid B containing a layered silicate compound.

  According to the surface treatment agent for silver or silver alloy of the present invention, a treatment layer free from cracks and cracks can be provided on the surface of silver or silver alloy, and is excellent in preventing discoloration (corrosion) of silver or silver alloy. In particular, it is possible to impart excellent discoloration resistance to the silver-plated surface.

  The liquid A preferably has a pH of 7 to 14, and the cationic electrolyte polymer is composed of an amino group, a quaternary ammonium group, and a quaternary phosphonium group whose ionic groups may form a salt. It is preferably 1 or more selected from the group. In this case, the concentration of the cationic electrolyte polymer in the liquid A can be 0.0003 mass% or more and 3 mass% or less. By making A liquid into such a structure, the discoloration resistance with respect to the surface of silver or a silver alloy can further be improved.

  The layered silicate compound preferably has an average long side length of 0.03 μm or more and 50 μm or less.

  The B liquid may further contain a silicate compound other than the layered silicate compound. When such a silicic acid compound is contained, the mass ratio of the silicic acid compound other than the laminar silicic acid compound to the laminar silicic acid compound is the silicic acid compound other than the laminar silicic acid compound / the lamellar silicic acid compound = 99/1. 1/99 is preferable.

  As the layered silicic acid compound, one of natural layered silicic acid compound, synthetic layered silicic acid compound and modified products thereof can be used alone or in combination of two or more.

  As the natural layered silicate compound, for example, the following layered silicate can be used. Examples include kaolin, talc-pyrophyllite, smectite, vermiculite, mica (mica), brittle mica, chlorite and the like. Representative species include, for example, lizardite, amesite, chrysotile, kaolinite, dickite, halloysite, talc, pyrophyllite, saponite, hectorite, montmorillonite, beidellite, three octahedral vermiculite, two octahedral vermiculite, Examples include phlogopite, biotite, lepidrite, illite, muscovite, paragonite, clintonite, margarite, clinochlore, chamosite, nimite, dombasite, kukeite, and suedeite. Examples of commercially available products include Kunipia (Kunimine Kogyo Co., Ltd., trade name, Kunipia F), wet pulverized mica (Yamaguchi Mica Co., Ltd., Y series, SA series) and the like.

  Examples of the synthetic layered silicate compound include fluorine phlogopite, potassium tetrasilicon mica, sodium tetrasilicon mica, Na teniolite, Li teniolite, montmorillonite, saponite, hectorite, and stevensite. Commercially available products include micro mica, somasif (trade name, MEB-3, manufactured by Corp Chemical Co., Ltd.), lucentite (trade name, SWN manufactured by Corp Chemical Co., Ltd.), swelling mica sol (manufactured by Topy Industries, NTS-10, NTS-5) and the like.

  Examples of the modified product of the synthetic layered silicate compound include commercially available products such as Somasif (trade name, MAE, manufactured by Corp Chemical), Lucentite (trade name, SPN, manufactured by Corp Chemical), and the like.

Silicate compounds other than the layered silicate compounds are compounds represented by the general formula M ₂ O · nSiO ₂ (n = 0.5 to 4.0, M represents an alkali metal of Li, Na, or K). Of these, one or more are preferable.

  The present invention also includes a substrate, a light reflection layer made of silver or a silver alloy provided on the substrate, and a treatment layer formed on the light reflection layer and formed from a surface treatment agent. I will provide a. The treatment layer includes a cationic electrolyte polymer layer formed from the liquid A of the surface treatment agent and a layered silicate compound layer formed from the liquid B of the surface treatment agent in this order as viewed from the light reflection layer side. It may be.

  The light reflecting substrate of the present invention can have excellent discoloration resistance by including a treatment layer formed from the surface treatment agent of the present invention on a light reflection layer made of silver or a silver alloy. Further, since the liquid B is in contact with the liquid A, the wettability on the surface of the silver or silver alloy is improved, so that a treatment layer free from cracks and cracks can be formed on the light reflecting layer. .

  The present invention also provides a light emitting device including a light reflecting substrate and a light emitting diode disposed on a processing layer of the light reflecting substrate. The light emitting device may further include a sealing layer made of a transparent resin formed on the treatment layer so as to cover the light emitting diode. From the viewpoint of gas barrier properties, the transparent resin is preferably a silicone resin or an epoxy resin.

  The surface of the light reflecting layer facing the treatment layer may be a rough surface (for example, a surface having an uneven shape). Examples of the surface having an uneven shape include a surface plated by a vapor deposition method.

  The present invention also provides a method for producing a light emitting device, wherein a cationic electrolyte polymer layer and a layered silicate compound layer are formed on a light reflecting layer by sequentially contacting a solution A and a solution B of a surface treatment agent. In this case, it is preferable to form a layered silicic acid compound layer from the B liquid after forming the cationic electrolyte polymer layer by removing the volatile components in the A liquid.

  The surface treatment agent includes a cationic electrolyte polymer, layered silicate compound particles alone or a mixture of layered silicate compound particles and a silicate compound other than the layered silicate compound, and the surface treatment agent is silver or By coating the light reflecting layer made of a silver alloy and then removing the solvent, excellent discoloration resistance can be imparted particularly to the silver-plated surface. The layered silicic acid compound particles contained in the surface treatment agent are laminated on a light reflecting layer made of silver or a silver alloy, so that, for example, hydrogen sulfide in the atmosphere which is a discoloration factor of silver or a silver alloy Gas shielding properties are improved, and discoloration resistance can be imparted to a light reflecting layer made of silver or a silver alloy.

  Further, the silicate compound other than the layered silicate compound contained in the surface treatment agent has an action of improving the adhesion between the layered silicate compound particles and silver or a silver alloy. That is, by containing a silicate compound other than the layered silicate compound, the stress at the interface between the layered silicate compound particles and the silver or silver alloy is relieved, and the adhesive force is further improved. As a result, it is possible to achieve higher gas barrier properties and more reliably prevent discoloration of the light reflecting layer made of silver or a silver alloy.

  ADVANTAGE OF THE INVENTION According to this invention, the light-emitting device which has a light reflection board | substrate excellent in the color fastness, and is hard to fall in emitted light intensity can be provided.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the surface treating agent which can give the outstanding discoloration resistance to the surface of various silver or silver alloys. In addition, it is possible to provide a light-reflecting substrate excellent in discoloration resistance and a light-emitting device in which light emission intensity is hardly reduced, which is provided with a treatment layer that is formed from the surface treatment agent and has no cracks and cracks.

1 is a schematic cross-sectional view showing an embodiment of a light emitting device according to the present invention.

  Hereinafter, although the present invention is explained in detail, the present invention is not limited to the following embodiments.

  The silver or silver alloy surface treatment agent of the present invention is characterized by comprising a liquid A containing a cationic electrolyte polymer and a liquid B containing a layered silicate compound. Examples of the silver alloy include silver-bismuth alloy, silver-neodymium alloy, silver-copper alloy, silver-magnesium alloy, silver-zinc alloy, silver-tin alloy, silver-indium alloy, silver-titanium alloy, silver-zirconium. An alloy, a silver-gold alloy, a silver-palladium alloy, a silver-platinum alloy, and the like can be given. The cationic electrolyte polymer contained in the liquid A is a cationic polymer that can be ionized in water and has an ionic group that generates a cation. This ionic group preferably contains one or more selected from the group consisting of a primary amino group, a secondary amino group, a tertiary amino group, a quaternary ammonium group and a quaternary phosphonium group. The primary to tertiary amino groups may form a salt.

  Examples of the cationic electrolyte polymer include polyethyleneimine (PEI) and its quaternized product, polyallylamine and its quaternized product, polyallylamine hydrochloride (PAH), polydiallyldimethylammonium chloride (PDDA), and polyvinylpyridine (PVP). , Polylysine, polyacrylamide, polypyrrole, polyaniline, polyparaphenylene (+), polyparaphenylene vinylene, polyethylimine, and a copolymer or a salt containing at least one of these may be used. it can.

  More specifically, as the cationic electrolyte polymer, for example, polyallylamine amide sulfate, copolymer of allylamine hydrochloride and diallylamine hydrochloride, copolymer of allylamine hydrochloride and dimethylallylamine hydrochloride, allylamine hydrochloride and other Copolymer, partially methoxycarbonylated allylamine polymer, partially methylcarbonylated allylamine acetate polymer, diallylamine hydrochloride polymer, methyldiallylamine hydrochloride polymer, methyldiallylamine amide sulfate polymer, methyldiallylamine acetate polymer, Copolymer of diallylamine hydrochloride and sulfur dioxide, copolymer of diallylamine acetate and sulfur dioxide, copolymer of diallylmethylethylammonium ethyl sulfate and sulfur dioxide, methyldiallylamine hydrochloride and sulfur dioxide Polymers, copolymers of diallyldimethylammonium chloride and sulfur dioxide, copolymers of diallyldimethylammonium chloride and acrylamide, copolymers of diallyldimethylammonium chloride and diallylamine hydrochloride derivatives, dimethylamine and epichlorohydrin And a copolymer of dimethylamine, ethylenediamine and epichlorohydrin, a copolymer of polyamide polyamine and epichlorohydrin, and the like.

  These cationic electrolyte polymers are both water-soluble or soluble in a mixture of water and an organic solvent, and the weight average molecular weight of the cationic electrolyte polymer depends on the type of electrolyte polymer used. 400-300,000 is preferred. Here, the weight average molecular weight of the cationic electrolyte polymer is a value converted from a calibration curve using standard polystyrene by gel permeation chromatography (GPC).

  The concentration of the cationic electrolyte polymer is preferably 0.0003% by mass or more and 3% by mass or less, more preferably 0.001% by mass or more and 1% by mass or less, and 0.01% by mass or more and 1% by mass based on the total amount of the liquid A. A mass% or less is more preferable. If the concentration of the cationic electrolyte polymer is too low, the cationic electrolyte polymer layer cannot be formed on the surface of the light reflecting layer made of silver or a silver alloy, and if the concentration is too high, the excess cationic electrolyte polymer generates aggregates. Therefore, the transparency and flatness of the layered silicate compound layer formed thereon are impaired.

  Moreover, 7 or more and 14 or less are preferable, as for pH of the A liquid containing a cationic electrolyte polymer, 9 or more and 12 or less are more preferable, and 9 or more and 11 or less are more preferable. If the pH is too low, adsorption of the cationic electrolyte polymer on the surface of silver or the silver alloy is difficult to occur. If the pH is too high, the surface of the silver or silver alloy is likely to be affected.

  Liquid B contains a layered silicate compound such as a layered silicate. The layered silicate compound particles preferably have a thickness of about 1 nm, and preferably have a plate-like shape having an average long side length of 0.03 μm or more and 50 μm or less. The layered silicate compound has a property of swelling and dispersing in a solvent by mixing with a solvent such as water and alcohol.

  Moreover, it is preferable that B liquid contains silicic acid compounds other than the said layered silicic acid compound. Similar to the layered silicate compound, such a silicate compound also has a property of being swollen by being mixed with a solvent such as water and alcohol and dispersed in the solvent.

  The mass ratio of the silicate compound other than the layered silicate compound to the layered silicate compound contained in the liquid B is silicate compound other than the layered silicate compound / layered silicate compound = 99/1 to 1/99. Preferably there is. In addition, mass ratio is ratio in the solid content state which does not contain a solvent etc.

  When the solid content of the silicate compound other than the layered silicate compound relative to the layered silicate compound is 1 part by mass or more with respect to 99 parts by mass of the layered silicate compound, the present silicate compound is converted into silver or a silver alloy. Therefore, the adhesion of the layered silicate compound particles onto the light reflecting layer made of silver or a silver alloy is improved. As a result, the gas permeation amount of hydrogen sulfide or the like from the adhesion interface is reduced, and the discoloration suppressing effect of silver or a silver alloy can be further improved.

  Further, when the solid content of the layered silicate compound is 1 part by mass or more with respect to 99 parts by mass of the silicate compound other than the layered silicate compound, the content of the layered silicate compound particles having gas shielding properties is increased. Become more. As a result, the gas permeation amount of hydrogen sulfide or the like is further reduced, and the discoloration suppressing effect of silver or a silver alloy is further improved.

  In addition, from the viewpoint of improving the adhesion to silver or a silver alloy and improving the gas shielding properties such as hydrogen sulfide, the mass ratio of the silicate compound other than the layered silicate compound to the layered silicate compound is other than the layered silicate compound. The silicate compound / layered silicate compound is more preferably 95/5 to 5/95, and further preferably 80/20 to 20/80.

  By laminating layered silicate compound particles having a flat plate shape with a thickness of about 1 nm and an average long side length of 0.03 μm to 50 μm on a light reflecting layer made of silver or a silver alloy, for example, sulfide It exhibits gas shielding properties such as hydrogen.

  From the viewpoint of maintaining the gas shielding property and the original gloss of silver or silver alloy, the layered silicate compound particles contained in the liquid B preferably have an average long side length of 0.03 μm or more and 50 μm or less. The side length is more preferably 0.05 μm or more and 50 μm or less, and the average long side length is further preferably 0.10 μm or more and 50 μm or less.

  The average long side length of the layered silicate compound particles can be measured by using, for example, a transmission electron microscope. The average long side length is the average length of the long side portion of the flat plate-like particles. Specifically, the average long side length is defined as the average of the measured values of the long side portions of all 30 layered silicate compounds in the 250,000-fold image.

As a silicate compound other than the layered silicate compound, a compound represented by a general formula M ₂ O.nSiO ₂ (n = 0.5 to 4.0, M represents an alkali metal of Li, Na, or K). Of these, one or more can be suitably used.

  In addition, as a solvent used for B liquid, water, a water-soluble liquid, etc. are mentioned, for example.

  As water, for example, ultrapure water is used. Ultrapure water is water that contains a very small amount of ionic impurities, and has an electrical resistivity (specific resistance, MΩ · cm) (JIS K0552) as an index, and has a theoretical value of 15 MΩ · cm or more at 25 ° C., Preferably, water of 18 MΩ · cm or more can be used.

  Examples of the water-soluble liquid include polar solvents such as alcohol. Specific examples of alcohol and other water-soluble liquids include ethanol, methanol, isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, t-butyl alcohol, dioxane, acetone, acetonitrile, diethylamine, pyridine, N, N- Dimethylformamide, dimethylsulfoxide, sulfolane, N-methylpyrrolidone, propylene carbonate, γ-butyrolactone, formamide, allyl alcohol, acrylic acid, acetic acid, ethylene glycol, propylene glycol, glycerin, methacrylic acid, butyric acid, trimethylamine, triethylamine, ammonia, diethyl A liquid such as sulfite can be employed. A water-soluble liquid refers to a liquid that maintains a uniform appearance even after the flow has subsided when gently mixed with pure water of the same volume at a temperature of 20 ° C. at 1 atm. A water-soluble liquid can be used individually by 1 type or in mixture of 2 or more types.

  In the present embodiment, when a mixture of water and a water-soluble liquid is used as a solvent, the mass ratio of water to the water-soluble liquid is 99 / It is preferably 1 to 5/95, more preferably 95/5 to 10/80, and still more preferably 90/10 to 50/50.

  By using the surface treatment agent according to the present embodiment, a substrate and a light reflection layer made of silver or a silver alloy provided on the substrate are provided, and the surface treatment agent contains the surface of the light reflection layer. It is possible to provide a light reflecting substrate on which a treatment layer made of a solid component is formed. That is, specifically, by sequentially laminating the liquid A and liquid B of the surface treatment agent on the light reflection layer made of silver or a silver alloy provided on the substrate, the solid component contained in the surface treatment agent is removed. A light-reflecting substrate can be produced in which a treatment layer is provided. After the surface treatment agent of the present embodiment is applied on the light reflection layer made of silver or silver alloy, the layered silica contained in the surface treatment agent on the light reflection layer made of silver or silver alloy is removed by removing the solvent. A layer containing a silicate compound other than the acid compound and the layered silicate compound can be formed.

  As a method for applying the surface treating agent according to the present embodiment to silver or a silver alloy, for example, methods such as bar coating, dip coating, spin coating, spray coating, and potting can be suitably used.

  In addition, as a method for removing the solvent from the surface treatment agent, drying can be suitably used, and the drying temperature is not particularly limited as long as the drying temperature is room temperature or higher. In the present embodiment, the room temperature is 20 to 25 ° C.

  In the present embodiment, it is possible to provide a light emitting device including the light reflecting substrate and a light emitting diode disposed on the processing layer of the light reflecting substrate. Specifically, a light emitting diode is mounted on a processing layer of a light reflecting substrate in which a light reflecting layer made of silver or a silver alloy having a processing layer formed of a surface treatment agent is formed on the substrate. A surface treatment agent is applied by a method, or a method in which a light-emitting diode is mounted on a light reflection substrate including a light reflection layer made of silver or a silver alloy, and then a surface treatment agent is applied onto the light reflection layer and a solvent is removed. It is possible to provide a light emitting device including a light reflecting substrate including a treatment layer made of a contained solid component.

  FIG. 1 is a schematic cross-sectional view showing an embodiment of a light emitting device according to this embodiment. A light emitting device 20 shown in FIG. 1 includes a substrate 1, a light reflection layer 3 made of silver or a silver alloy provided on the substrate 1, a treatment layer 5 provided on the light reflection layer 3, and a treatment layer 5. The light-emitting diode 7 is provided on the top, and the sealing layer 10 is provided on the treatment layer 5 so as to cover the light-emitting diode 7. The sealing layer 10 is formed from a transparent resin.

  Note that in the light-emitting device, the light-emitting diode may be provided after the treatment layer is formed, or the treatment layer may be formed after the light-emitting diode is provided.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further more concretely, this invention is not limited to a following example.

<Combination of steven sites>
(Synthesis example)
20 ml of nitric acid was added to a dispersion obtained by mixing 60 g of colloidal silica (Ludox ™ 50, manufactured by SigmaAldrich) and 120 ml of distilled water. A solution prepared by mixing 91 g of magnesium nitrate (primary reagent) and 128 ml of distilled water was added thereto, and ammonia water (28 mass% aqueous solution) was slowly added dropwise thereto while stirring. The dripping was stopped when the pH reached 10, and the mixture was aged at room temperature overnight to obtain a uniform composite precipitate. Thereafter, water washing by adding distilled water, shaking, and solid-liquid separation was repeated until the ammonia odor disappeared. 25.4 ml of a 10% by weight lithium hydroxide aqueous solution was added to the well-mixed homogeneous composite precipitation dispersion and thoroughly mixed to obtain a starting raw material slurry. The starting material slurry was charged into an autoclave and hydrothermally reacted at 200 ° C. for 48 hours. After cooling, the reaction product in the autoclave was taken out, dried at 60 ° C., and then pulverized to obtain a smectite classified as a steven site.
Example 1

  The liquid A was prepared by adjusting the concentration of polydiallyldimethylammonium chloride (PDDA, manufactured by Aldrich) to 0.0028% by mass, adjusting the pH with a 0.1% by weight sodium carbonate aqueous solution, and adjusting the pH to 10. Used as a cationic electrolyte polymer solution. As the liquid B, 1 g of stevensite having an average long side length of 100 nm obtained in the synthesis example was used as a layered silicate compound, and distilled water was added to make the total weight 100 g, followed by a rotation / revolution mixer (Sinky ARE-310) manufactured by the company, mixed at 2000 rpm for 10 minutes, and defoamed at 2200 rpm for 10 minutes to obtain a liquid B of 1% by mass of synthetic smectite having an average long side length of 1007 nm.

<Application of surface treatment agent on light reflecting substrate>
Using a soda glass slide glass as a substrate and applying 100 parts of silver on the light-reflective substrate having a thickness of 100 nm deposited on the light reflective substrate, the above-mentioned solution A was applied using a bar coater with a wet thickness of 12 μm. The water on the surface was removed and dried. Thereafter, 1% by mass of the above-mentioned B solution was applied, and then allowed to stand at 70 ° C. for 5 minutes to remove water as a solvent to obtain a light reflecting substrate having a layered silicate compound layer on the surface. In addition, wet thickness is the thickness immediately after application | coating of the surface treating agent before removing a solvent.

  <Application of surface treatment agent to light emitting device>

  On the light reflection substrate, a light emitting diode chip having an emission wavelength of 467.5 nm to 470 nm and a cavity capacity of 3.7 μL was connected with a gold wire to produce a light emitting device. Thereafter, 3 μL of the solution A was dropped on the light emitting device with a micropipette, and the solvent was removed by drying at 70 ° C. for 5 minutes. Further, 1% by mass of the solution B was potted. That is, 3 μL was dropped with a micropipette and dried at 70 ° C. for 5 minutes to remove water as a solvent to obtain a light emitting device having a layered silicate compound layer on the surface.

<Hydrogen sulfide gas resistance evaluation of a light reflective substrate coated with a surface treatment agent>
First, the visible light reflectance at a wavelength of 550 nm of the light reflecting substrate produced by the above method was measured using a spectrophotometer (JASCO, V-570), and [reflectance before hydrogen sulfide exposure (%)] did. The light reflecting substrate was allowed to stand in a 10 ppm hydrogen sulfide gas stream, 40 ° C., 90% RH (relative humidity) for 96 hours, and then the visible light reflectance at a wavelength of 550 nm was measured. %)].

  [Reflectivity before exposure to hydrogen sulfide]-[Reflectivity after exposure to hydrogen sulfide] = [Reflectance reduction rate (%)]. When the reflection reduction rate is within 20%, the resistance to hydrogen sulfide gas is "Yes", and 20% The case where it exceeded was evaluated as "no hydrogen sulfide gas resistance".

<Hydrogen sulfide gas resistance evaluation of light emitting device coated with surface treatment agent>
The light emitting device coated with the surface treatment agent by the above method emits light at a forward current of 20 mA and a forward voltage of 3.3 V, and emits light with an exposure time of 30 milliseconds using a multiphotometer (MCPD-3700, manufactured by Otsuka Electronics Co., Ltd.). The intensity was measured and was defined as [emission intensity before exposure to hydrogen sulfide]. The light emitting device was allowed to stand in a 10 ppm hydrogen sulfide gas stream, 40 ° C., 90% RH (relative humidity) for 96 hours, and then emitted with a forward current of 20 mA and a forward voltage of 3.3 V, and exposed using a multiphotometer. The luminescence intensity was measured at a time of 30 milliseconds and was defined as [luminescence intensity after exposure to hydrogen sulfide].

  ([Emission intensity after exposure to hydrogen sulfide] / [Emission intensity before exposure to hydrogen sulfide]) × 100 = [Emission intensity maintenance rate (%)], and when the emission intensity maintenance rate is 80% or more, hydrogen sulfide gas resistance “ The case of “Yes” and less than 80% was evaluated as “No” for hydrogen sulfide gas resistance.

(Example 2)
A surface treatment agent was prepared in the same manner as in Example 1 except that smectite having an average long side length of 950 nm was used, and evaluation was performed in the same manner as in Example 1.

(Example 3)
A surface treatment agent was prepared in the same manner as in Example 1 except that smectite having an average long side length of 780 nm was used, and evaluation was performed in the same manner as in Example 1.

Example 4
A surface treatment agent was prepared in the same manner as in Example 1 except that smectite having an average long side length of 190 nm was used, and evaluation was performed in the same manner as in Example 1.

(Example 5)
A surface treatment agent was prepared in the same manner as in Example 1 except that smectite having an average long side length of 178 nm was used, and evaluation was performed in the same manner as in Example 1.

(Example 6)
A surface treatment agent was prepared in the same manner as in Example 1 except that smectite having an average long side length of 140 nm was used, and evaluation was performed in the same manner as in Example 1.

(Example 7)
A surface treatment agent was prepared in the same manner as in Example 1 except that smectite having an average long side length of 124 nm was used, and evaluation was performed in the same manner as in Example 1.

(Example 8)
A surface treatment agent was prepared in the same manner as in Example 1 except that smectite having an average long side length of 120 nm was used, and evaluation was performed in the same manner as in Example 1.

Example 9
A surface treatment agent was prepared in the same manner as in Example 1 except that smectite having an average long side length of 100 nm was used, and evaluation was performed in the same manner as in Example 1.

(Example 10)
0.99 g containing a steven site having an average long side length of 1007 nm obtained in the synthesis example was used as a layered silicate compound, and 0.01 g of lithium silicate (manufactured by Nissan Chemical Industries, Ltd., LSS35) was added to a silica other than the layered silicate compound. A surface treatment agent was prepared in the same manner as in Example 1 except that each was used as an acid compound, and evaluation was performed in the same manner as in Example 1.

(Example 11)
A surface treatment agent was prepared in the same manner as in Example 10 except that smectite having an average long side length of 190 nm was used, and evaluation was performed in the same manner as in Example 1.

(Example 12)
A surface treatment agent was prepared in the same manner as in Example 10 except that smectite having an average long side length of 100 nm was used, and evaluation was performed in the same manner as in Example 1.

(Comparative Example 1)
A surface treatment agent was prepared in the same manner as in Example 1 except that the B solution was directly applied without using the A solution, and evaluation was performed in the same manner as in Example 1.

  As a result of evaluation, in Examples 1 to 12, the hydrogen sulfide gas resistance of the light reflecting substrate and the hydrogen sulfide gas resistance of the light emitting device were all “present”, whereas in the comparative examples, all were “none”. . Further, in all of Examples 1 to 12, it was confirmed by observation that the treatment layer formed from the surface treatment agent on the light reflecting substrate was free from cracks and cracks.

  According to the present invention, various silver or silver alloys, for example, silver or silver alloys used for lighting devices such as electronic parts and light-emitting diodes, etc. have excellent discoloration (corrosion) prevention properties, and particularly excellent discoloration resistance to silver-plated surfaces. It becomes possible to provide a surface treatment agent capable of imparting properties. Further, a substrate and a light reflecting layer made of silver or a silver alloy provided on the substrate are provided, and a treatment layer made of a surface treatment agent of silver or a silver alloy is provided on the surface of the light reflecting layer. It is possible to provide a light reflecting substrate. Furthermore, it is possible to provide a light emitting device including the light reflecting substrate and the light emitting diode.

  DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 3 ... Light reflection layer, 5 ... Processing layer, 7 ... Light emitting diode, 10 ... Sealing layer, 20 ... Light-emitting device.

Claims (16)

Liquid A containing a cationic electrolyte polymer;
A surface treatment agent of silver or a silver alloy, comprising a liquid B containing a layered silicate compound.   The surface treatment agent for silver or silver alloy according to claim 1, wherein the solution A has a pH of 7 to 14.   In the cationic electrolyte polymer, the ionic group is one or more selected from the group consisting of an amino group, a quaternary ammonium group and a quaternary phosphonium group which may form a salt. The surface treatment agent of the silver or silver alloy of description.   The said A liquid is a surface treatment agent of the silver or silver alloy as described in any one of Claims 1-3 whose density | concentration of the said cationic electrolyte polymer is 0.0003 mass% or more and 3 mass% or less.   The surface treatment agent for silver or silver alloy according to any one of claims 1 to 4, wherein the layered silicate compound has an average long side length of 0.03 µm or more and 50 µm or less.   The said B liquid is a surface treatment agent of the silver or silver alloy as described in any one of Claims 1-5 which contains silicic acid compounds other than the said layered silicic acid compound further.   The silver or silver alloy surface treatment agent according to claim 6, wherein a mass ratio of the silicate compound other than the layered silicate compound to the layered silicate compound is 99/1 to 1/99. Among the compounds represented by M ₂ O · nSiO ₂ (n = 0.5 to 4.0, M represents an alkali metal of Li, Na, or K), the silicate compound other than the layered silicate compound. The surface treatment agent for silver or silver alloy according to claim 6 or 7, wherein the surface treatment agent is one or more.   The surface of the silver or silver alloy as described in any one of Claims 1-8 provided on the board | substrate, the light reflection layer which consists of silver or a silver alloy provided on this board | substrate, and this light reflection layer And a treatment layer formed from the treatment agent.   The treatment layer includes a cationic electrolyte polymer layer formed from the liquid A of the surface treatment agent and a layered silicate compound layer formed from the liquid B of the surface treatment agent when viewed from the light reflection layer side. The light reflection board according to claim 9 provided in this order.   A light emitting device comprising: the light reflecting substrate according to claim 9 or 10; and a light emitting diode disposed on the processing layer of the light reflecting substrate.   The light emitting device according to claim 11, further comprising a sealing layer made of a transparent resin formed on the processing layer so as to cover the light emitting diode.   The light emitting device according to claim 12, wherein the transparent resin is a silicone resin or an epoxy resin.   The light emitting device according to any one of claims 11 to 13, wherein a surface of the light reflecting layer facing the processing layer is a rough surface. It is a manufacturing method which manufactures the light-emitting device as described in any one of Claims 11-14,
A method for manufacturing a light emitting device, wherein a cationic electrolyte polymer layer and a layered silicate compound layer are formed by sequentially contacting the surface treatment agent A solution and the B solution on the light reflection layer.   The method for manufacturing a light-emitting device according to claim 15, wherein after forming the cationic electrolyte polymer layer by removing volatile components in the liquid A, the layered silicate compound layer is formed from the liquid B.

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