Abstract: A recording medium including, in the following order, a base, an ink-receiving layer containing inorganic particles, and a protective layer. The protective layer contains colloidal silica, gas phase process silica, and at least one kind of particles selected from resin particles and wet process silica particles. The average particle size of the at least one kind of particles is 1.5 ?m or more.

Abstract: A recording medium includes a substrate, a first ink receiving layer and a second ink receiving layer in that order. The first ink receiving layer contains at least one inorganic pigment selected from the group consisting of alumina, hydrated alumina and fumed silica, polyvinyl alcohol, and a boric acid compound. The second ink receiving layer contains fumed silica, particles having an average particle size in a specific range, polyvinyl alcohol, and a boric acid compound. The boric acid compound content in the first ink receiving layer is in a predetermined range, and the boric acid compound content in the second ink receiving layer is in a predetermined range. The particle content in the second ink receiving layer is in a predetermined range.

Abstract: A recording medium includes a substrate and an ink receiving layer that includes inorganic particles and a binder. The inorganic particles include fumed silica particles. The binder includes a resin having a glass transition temperature of 20° C. or less. The content of the binder in the ink receiving layer is 40% by mass or more of the content of the inorganic particles included in the ink receiving layer.

Abstract: A recording medium includes a substrate and an ink receiving layer that includes inorganic particles and a binder. The inorganic particles include at least one type of alumina particles selected from fumed alumina particles and hydrated alumina particles. The binder includes a resin having a glass transition temperature of 20° C. or less. The content of the binder in the ink receiving layer is 25% by mass or more of the content of the inorganic particles included in the ink receiving layer.

Abstract: A recording medium including a substrate and an ink receiving layer on the substrate, the ink receiving layer containing inorganic particles and a water-soluble resin. The recording medium has an HM1 of 40 N/mm2 or less and has a rate of change of HM2 to HM1 of 400% or less. HM1 is a Martens hardness when an indenter is pushed at a 500 mN load over 180 seconds from a surface of the recording medium into a 1 ?m depth in a thickness direction thereof. HM2 is a Martens hardness when the indenter is pushed up to a position where the indenter is not in contact with the surface and is then pushed at a 500 mN load over 180 seconds from a pressing starting position into a 1 ?m depth in the thickness direction at the same point as that at which the indenter is first pushed.

Abstract: A recording medium includes in this order a water-resistant substrate, a first ink receiving layer, and a second ink receiving layer that is the outermost layer. The first ink receiving layer contains a fumed silica and a binder. The second ink receiving layer contains a colloidal silica having an average primary particle diameter of 50 nm or more and 100 nm or less, and a polyvinyl alcohol having a silanol group.

Abstract: A recording medium including a first resin layer, a porous undercoating layer and a first ink-receiving layer provided in this order on one surface of a base and including a second resin layer and a second ink-receiving layer provided in this order on the other surface of the base, wherein 60° specular glossinesses of a surface of the first resin layer closer to the first ink-receiving layer and a surface of the second resin layer closer to the second ink-receiving layer are each 65% or more, and the porous undercoating layer has a thickness of 3 ?m or less.

Abstract: A recording medium includes a support and an ink-receiving layer. The ink-receiving layer contains alumina particles, silica particles and a binder. A composition analysis of the recording medium performed by X-ray photoelectron spectroscopy while etching is performed from a surface side to a support side provides a ratio of the amount of Si element to the total amount of Al element and Si element at an etching time of 0 minutes of 10 atomic percent or more and 90 atomic percent or less and a ratio of the amount of Si element to the total amount of Al element and Si element at an etching time of 5 minutes of 50 atomic percent or more.

Abstract: A recording medium includes a substrate, a first ink receiving layer and a second ink receiving layer in that order. The first ink receiving layer contains at least one inorganic pigment selected from the group consisting of alumina, hydrated alumina and fumed silica, polyvinyl alcohol, and a boric acid compound. The second ink receiving layer contains fumed silica, particles having an average particle size in a specific range, polyvinyl alcohol, and a boric acid compound. The boric acid compound content in the first ink receiving layer is in a predetermined range, and the boric acid compound content in the second ink receiving layer is in a predetermined range. The particle content in the second ink receiving layer is in a predetermined range.

Abstract: A recording medium including, in the following order, a base, an ink-receiving layer containing inorganic particles, and a protective layer. The protective layer contains colloidal silica, gas phase process silica, and at least one kind of particles selected from resin particles and wet process silica particles. The average particle size of the at least one kind of particles is 1.5 ?m or more.

Abstract: A recording medium including a first resin layer, a porous undercoating layer and a first ink-receiving layer provided in this order on one surface of a base and including a second resin layer and a second ink-receiving layer provided in this order on the other surface of the base, wherein 60° specular glossinesses of a surface of the first resin layer closer to the first ink-receiving layer and a surface of the second resin layer closer to the second ink-receiving layer are each 65% or more, and the porous undercoating layer has a thickness of 3 ?m or less.

Abstract: A recording medium includes a support and an ink-receiving layer. The ink-receiving layer contains alumina particles, silica particles and a binder. A composition analysis of the recording medium performed by X-ray photoelectron spectroscopy while etching is performed from a surface side to a support side provides a ratio of the amount of Si element to the total amount of Al element and Si element at an etching time of 0 minutes of 10 atomic percent or more and 90 atomic percent or less and a ratio of the amount of Si element to the total amount of Al element and Si element at an etching time of 5 minutes of 50 atomic percent or more.

Abstract: A recording medium includes a substrate and at least one ink-receiving layer, wherein an outermost ink-receiving layer of the recording medium contains inorganic particles, particles other than the inorganic particles, and a binder, the particles other than the inorganic particles have an average primary particle size of 30 nm or more and 100 nm or less, the outermost ink-receiving layer of the recording medium has a thickness of 5 ?m or more, 60% or more and 90% or less of the particles other than the inorganic particles in the outermost ink-receiving layer of the recording medium are present in a region 500 nm or less below the outermost surface of the recording medium, and the area ratio of a region containing the particles other than the inorganic particles to the outermost surface of the recording medium is 30% or more and 80% or less.

Abstract: A fault-spot locating method, comprising at a switching apparatus that includes an interface for connection to a master, which is a controlling object, and a plurality of ports for connection to a slave, which is a controlled object, providing another interface used to output information indicating an operation of the switching apparatus and received data, and causing the switching apparatus to transmit the information via the another interface, using a processor. And causing an apparatus that is capable of obtaining the information transmitted via the another interface to locate a spot where a fault has possibly occurred by using the information to check the received data and the operation of the switching apparatus caused by a command from the master, using the processor.

Abstract: A recording medium includes, in sequence, a support, a first ink-receiving layer containing a first inorganic particle and a first binder, a second ink-receiving layer containing a second inorganic particle and a second binder, and a third ink-receiving layer which is an outermost surface layer and contains a third inorganic particle, a third binder, and a particle different from the third inorganic particle and having an average secondary particle size of 1.0 to 20.0 ?m. A mass ratio of a content of the first binder to a content of the first inorganic particle is larger than a mass ratio of a content of the second binder to a content of the second inorganic particle. A content of the particle having the specific average secondary particle size is 0.5% by mass or more with respect to a content of the third inorganic particle.

Abstract: A recording medium includes a base paper, a polymer layer disposed on the base paper, and an ink-receiving layer disposed on the polymer layer. The base paper has a thickness of 50 ?m or more and 130 ?m or less. The polymer layer has a thickness of 20 ?m or more and 60 ?m or less. The polymer layer has an arithmetic average surface roughness Ra1 of 0.12 ?m or more and 0.18 ?m or less. The polymer layer has a roughness curve element average length RSm of 0.01 mm or more and 0.20 mm or less. The recording medium has an arithmetic average surface roughness Ra2 of 0.13 ?m or less.

Abstract: A recording medium includes, in sequence, a support, a first ink-receiving layer, and a second ink-receiving layer, in which a content of a boric acid in the first ink-receiving layer is 2.0% by mass or more and 7.0% by mass or less with respect to a content of a polyvinyl alcohol in the first ink-receiving layer, a content of a boric acid in the second ink-receiving layer is 10.0% by mass or more and 30.0% by mass or less with respect to a content of a polyvinyl alcohol in the second ink-receiving layer, an outermost surface layer of the recording medium has a content of particles of 0.5% by mass or more and 5.0% by mass or less, the particles having an average secondary particle size of 1.0 ?m or more and 20.0 ?m or less with respect to a content of an inorganic pigment.

Abstract: A recording medium includes, in sequence, a support, a first ink-receiving layer containing a first inorganic particle and a first binder, a second ink-receiving layer containing a second inorganic particle and a second binder, and a third ink-receiving layer which is an outermost surface layer and contains a third inorganic particle, a third binder, and a particle different from the third inorganic particle and having an average secondary particle size of 1.0 to 20.0 ?m. A mass ratio of a content of the first binder to a content of the first inorganic particle is larger than a mass ratio of a content of the second binder to a content of the second inorganic particle. A content of the particle having the specific average secondary particle size is 0.5% by mass or more with respect to a content of the third inorganic particle.

Abstract: A recording medium includes a base and at least one ink-receiving layer. A first ink-receiving layer that is at least one ink-receiving layer contains inorganic particles having an average primary particle size of 1 ?m or less and inorganic particles coated with a metal oxide. The inorganic particles coated with the metal oxide have an average primary particle size of 15.0 ?m or more. When the maximum of a FLOP value of the recording medium is denoted by FLOPMax and the minimum of the FLOP value is denoted by FLOPMin, the FLOPMin is 2.5 or more and a value of FLOPMin/FLOPMax is 0.80 or more and 1.00 or less.

Abstract: A recording medium includes a base paper, a polymer layer disposed on the base paper, and an ink-receiving layer disposed on the polymer layer. The base paper has a thickness of 50 ?m or more and 130 ?m or less. The polymer layer has a thickness of 20 ?m or more and 60 ?m or less. The polymer layer has an arithmetic average surface roughness Ra1 of 0.12 ?m or more and 0.18 ?m or less. The polymer layer has a roughness curve element average length RSm of 0.01 mm or more and 0.20 mm or less. The recording medium has an arithmetic average surface roughness Ra2 of 0.13 ?m or less.