Patent application number | Description | Published |
20130122786 | RINSING AGENT, AND METHOD FOR PRODUCTION OF HARD DISK SUBSTRATE - Provided are a rinsing agent to produce a hard disk substrate free from remaining abrasive grains as well as a pit defect on the surface thereof and a method for production of a hard disk substrate using such a rinsing agent. A rinsing agent of the present invention is rinsing solution containing colloidal silica as abrasive grains. Letting that the colloidal silica abrasive grains have a concentration C and an average grain size R (C and R are represented in weight % and nm, respectively), the concentration C and the average grain size R of the colloidal silica abrasive grains have a relation matching the following Expression (1): | 05-16-2013 |
20130196178 | METHOD FOR PRODUCTION OF HARD DISK SUBSTRATE AND HARD DISK SUBSTRATE - Provided are a method for production of a hard disk substrate capable of obtaining a smooth surface of a plating film by electroless NiP plating that is not degraded in, but exhibits corrosion resistance against, an acid solution and such a hard disk substrate. The method for production of a hard disk substrate including an electroless NiP plating film, includes the steps of: a first plating step of immersing a substrate in first electroless NiP plating bath containing an additive having a smoothing effect to form a lower layer of the electroless NiP plating film on a surface of the substrate, the lower layer having an average surface roughness smaller than an average surface roughness of the surface; and a second plating step of immersing the substrate on which the lower layer of the electroless NiP plating film is formed in the first plating step in a second electroless NiP plating bath to form an upper layer of the electroless NiP plating film, the upper layer having corrosion resistance against an acid solution. The resulting plating film has a smooth surface that is not degraded in, but exhibits corrosion resistance against, an acid solution. | 08-01-2013 |
20130309405 | PLATING PRETREATMENT SOLUTION AND METHOD FOR PRODUCING ALUMINUM SUBSTRATE FOR HARD DISK DEVICES USING SAME - An object of the invention is to provide a plating pretreatment solution that can convert the surface of an aluminum substrate for hard disk devices into a surface suitable for electroless nickel plating, and a method for producing an aluminum substrate for hard disk devices using the same. The plating pretreatment solution of the present invention used for a plating pretreatment in production of an aluminum substrate for hard disk devices has an iron ion concentration of 0.1 g/l to 1.0 g/l and a nitric acid concentration of 2.0 wt % to 12.0 wt %. This plating pretreatment solution is used for a pretreatment of a plating step in which electroless nickel plating is applied to an aluminum substrate for hard disk devices. Accordingly, the surface of the aluminum substrate for hard disk devices is converted into a surface suitable for electroless Ni plating, and a smooth surface of a plated film is obtained by suppressing generation of waviness, nodules, and pits on the plated surface when electroless nickel plating is performed in the plating step. | 11-21-2013 |
20150064347 | METHOD FOR PRODUCING HARD DISK SUBSTRATE - An object of the present invention is to obtain a hard disk substrate that can have a smooth surface of a plating film through electroless NiP plating and does not have deteriorated corrosion resistance against acid solutions. A method for producing a hard disk substrate of the present invention includes a first plating step of immersing a substrate in a first electroless NiP plating bath containing an additive with leveling action, thereby forming a lower layer of the electroless NiP plating film on a surface of the substrate, the lower layer having smaller average surface roughness than the surface; and a second plating step of immersing the substrate that has the lower layer of the electroless NiP plating film formed thereon through the first plating step in a second electroless NiP plating bath, thereby forming an upper layer of the electroless NiP plating film, the upper layer having corrosion resistance against acid solutions. Exposure of the lower layer to the atmosphere is suppressed in the period during transition from the first plating step to the second plating step. | 03-05-2015 |
20150099143 | METHOD FOR PRODUCTION OF HARD DISK SUBSTRATE AND HARD DISK SUBSTRATE - Provided are a method for production of a hard disk substrate capable of obtaining a smooth surface of a plating film by electroless NiP plating that is not degraded in corrosion resistance against the acid solution and such a hard disk substrate. According to the present invention, a method for production of a hard disk substrate including an electroless NiP plating film, includes the steps of: a first plating step of immersing a substrate in first electroless NiP plating bath containing an additive having a smoothing effect to form a lower layer of the electroless NiP plating film on a surface of the substrate, the lower layer having average surface roughness smaller than an average surface roughness of the surface; and a second plating step of immersing the substrate on which the lower layer of the electroless NiP plating film is formed in the first plating step in second electroless NiP plating bath to form an upper layer of the electroless NiP plating film, the upper layer having corrosion resistance against the acid solution. Thereby, a plating film having a smooth surface that is not degraded in corrosion resistance against the acid solution can be obtained. | 04-09-2015 |
20150125598 | METHOD FOR PRODUCING HARD DISK SUBSTRATE - An object of the present invention is to obtain a hard disk substrate that can have a smooth surface of a plating film through electroless NiP plating and does not have deteriorated corrosion resistance against acid solutions. A method for producing a hard disk substrate of the present invention is a method for producing a hard disk substrate with an electroless NiP plating film, the method including immersing a substrate in a first electroless NiP plating bath containing an additive with leveling action, thereby forming a lower layer of the electroless NiP plating film on a surface of the substrate, the lower layer having smaller average surface roughness than the surface; and immersing the substrate that has the lower layer of the electroless NiP plating film formed thereon through the first plating step in a second electroless NiP plating bath, thereby forming an upper layer of the electroless NiP plating film, the upper layer having corrosion resistance against acid solutions and having a thickness of greater than or equal to 4 μm. | 05-07-2015 |
20150176134 | METHOD OF ELECTROLESS GOLD PLATING AND GOLD PLATE COATED MATERIAL - There is provided a method of electroless gold plating, wherein the method includes a step of forming an underlying alloy layer on a base material and a step of forming a gold plate layer directly on the underlying alloy layer by means of electroless reduction plating using a cyanide-free gold plating bath, wherein the method is characterized in that the underlying alloy layer is formed of an M1-M2-M3 alloy (where M1 is at least one element selected from Ni, Fe, Co, Cu, Zn and Sn, M2 is at least one element selected from Pd, Re, Pt, Rh, Ag and Ru, and M3 is at least one element selected from P and B). | 06-25-2015 |
20150340714 | SEPARATOR FOR FUEL CELLS, FUEL CELL, FUEL CELL STACK, AND METHOD OF MANUFACTURING SEPARATOR FOR FUEL CELLS - A separator for fuel cells is provided. The separator includes: a base material; an underlying plate layer formed on the base material; and a gold plate layer formed on the underlying plate layer by means of electroless plating. The separator is characterized in that a face of the underlying plate layer facing the gold plate layer has an arithmetic average roughness Ra of 80 nm or less. According to the present invention, there can be provided a separator for fuel cells in which the gold plate layer can be uniformly formed for irregular parts that constitute gas flow channels and the occurrence of unformed parts and pinholes in the gold plate layer is prevented without increasing the film thickness of the gold plate layer and which is excellent in the corrosion resistance and the conductivity. | 11-26-2015 |