A polyimide precursor resin composition for forming a flexible device substrate, including a polyamic acid having a structure obtained from a tetracarboxylic acid component including at least one of 3,3,4,4-biphenyltetracarboxylic dianhydride and pyromellitic dianhydride, a diamine component including at least one of paraphenylene diamine and 4,4-diaminodiphenyl ether, and a carboxylic acid monoanhydride, the polyamic acid satisfying equations (1) and (2) below:

0.97X/Y<1.00Equation (1)

0.5(Z/2)/(YX)1.05Equation (2)

in which X represents a number of moles of tetracarboxylic acid component, Y represents a number of moles of diamine component, and Z represents a number of moles of the carboxylic acid monoanhydride.

The coated glass sheet of the present invention includes: a glass sheet; and a coating film provided on at least one principal surface of the glass sheet and having a smooth surface. The coating film includes: isolated closed pores present within the coating film; and a matrix. The coating film is substantially free of open pores open at the surface of the coating film. For the coated glass sheet of the present invention, a transmittance gain is 2.5% or more, the transmittance gain being calculated by subtracting an average transmittance of the glass sheet as determined by applying light having wavelengths of 380 to 1100 nm to the glass sheet in the absence of the coating film on the surface of the glass sheet from an average transmittance of the coated glass sheet as determined by applying light having the wavelengths to the coated glass sheet from a side on which the coating film lies.

A method for forming a self-cleaning coating, comprises providing a first dispersion comprising plasmonic nanoparticles by suspending plasmonic nanoparticles in an organic medium and providing a second dispersion comprising a precursor of a photocatalytic matrix in an organic medium. The method further comprises forming a mixture of the first and second dispersion and coating the mixture on a surface. The method also comprises calcining the coated mixture.

A chalcopyrite compound-based thin film in which an alkali metal is incorporated, and a method of fabricating the same are provided. The chalcopyrite compound-based thin film in which an alkali metal is incorporated may have improved film characteristics such as excellent chalcopyrite crystal characteristics and improved surface characteristics, and may exhibit improved optical characteristics by control of the distribution of constituent elements in the chalcopyrite compound layer. Accordingly, performance of a solar cell including the chalcopyrite compound-based thin film may be improved. The chalcopyrite compound-based thin film may be easily fabricated through a solution process.

A surface coating material includes a first material and a second material having a different structure. The first material includes a linking group represented by *(CF.sub.2).sub.nO* between two terminal ends, where one terminal end is a trifluoroalkoxy group and another terminal end is a silane group. The second material includes an oxyalkylene group or a *NH* linking group between two terminal ends, where one terminal end is an alkoxy group or an amino group, and another terminal end is a silane group. The first material is included in the surface coating material in an amount of less than or equal to about 5 mol % relative to a total amount (100 mol %) of the first material and the second material in the surface coating material.

The coated glass sheet of the present invention includes: a glass sheet; and a coating film provided on at least one principal surface of the glass sheet and having a smooth surface. The coating film includes: isolated closed pores present within the coating film; and a matrix. The coating film is substantially free of open pores open at the surface of the coating film. For the coated glass sheet of the present invention, a transmittance gain is 2.5% or more, the transmittance gain being calculated by subtracting an average transmittance of the glass sheet as determined by applying light having wavelengths of 380 to 1100 nm to the glass sheet in the absence of the coating film on the surface of the glass sheet from an average transmittance of the coated glass sheet as determined by applying light having the wavelengths to the coated glass sheet from a side on which the coating film lies.

A substrate with a switchable surface has been developed that can rapidly switch its surface character such as between two distinct liquid-repellent modes: (1) a superhydrophobic mode and (2) a slippery mode. Such surfaces have demonstrated adaptive liquid repellency and water harvesting capabilities.

An object of the present invention is to provide an ultraviolet and/or near-infrared shielding agent composition for transparent material using silicon compound-coated silicon-doped zinc oxide particles that are controlled in properties in an ultraviolet region and/or a near-infrared region. The present invention provides an ultraviolet and/or near-infrared shielding agent composition for transparent material used for a purpose of shielding ultraviolet rays and/or near-infrared rays, the ultraviolet and/or near-infrared shielding agent composition for transparent material featuring that the ultraviolet and/or near-infrared shielding agent contains silicon compound-coated silicon-doped zinc oxide particles, with which surfaces of silicon-doped zinc oxide particles that are zinc oxide particles doped with at least silicon are at least partially coated with a silicon compound.

An anti-forgery color conversion film includes a photonic crystal structure whose color is converted by an external stimulus such as a breath. The photonic crystal structure includes a first refractive index layer including a first polymer exhibiting a first refractive index; and a second refractive index layer which is alternately laminated with the first refractive index layer and includes a second polymer exhibiting a second refractive index. A consumer who purchases an article including the color conversion film may easily distinguish the authenticity of the article.

The present invention relates in part to short-wave IR (SWIR) materials comprising generic mixed salts of empirical formula A.sub.aB.sub.bM.sub.cX.sub.d that are composition-dependent, broadband, and tunable. These materials have unique light absorbance wavelengths from 0.4 to 2.6 m, including both the visible and SWIR. The preparation procedure for the SWIR materials is simple, including the use of widely available, cheap, and non-toxic precursors, unlike existing state of the art alloy SWIR materials. These novel materials have broad applications in security, surveillance, military, machine vision, photovoltaic solar cells, medical treatments, spectroscopy detector, and thermography. The present invention also relates to methods of fabricating a film comprising the composition of the invention and to photovoltaic stacks comprising the composition of the invention.