A mill blank for dental CAD/CAM for preparing a dental restoration by being installed in a CAD/CAM device, wherein, the mill blank for dental CAD/CAM has a columnar shape, has at least two recesses which includes a first recess opening to an upper surface of the mill blank and a second recess opening to a bottom surface of the mill blank and at least one notched portion in a circumference portion, the first recess and the second recess respectively include a first surface which is parallel to the upper surface and the bottom surface and a second surface which is a circumferential face concentric with the circumferential face of the mill blank and is vertical to the first surface, and the notched portion is composed of a surface parallel to the center axis of the columnar shape of the mill blank and contacts with the second surface.

A folding metal back plate includes a first plate portion, a second plate portion, and a folding plate portion connected to the first plate portion and the second plate portion. The folding plate portion has two first folding areas respectively disposed close to the first plate portion and the second plate portion, and a second folding area formed between the two first folding areas. The first folding area has multiple rows of spaced first openings. The second folding area has multiple rows of spaced second openings. Each first folding area constitutes a first unfolding length. The second folding area constitutes a second unfolding length. The first unfolding length of the first folding area is 0.2 to 0.5 times the second unfolding length of the second folding area.

A dental mill blank can be fabricated, through a milling process, into a highly aesthetic dental prosthesis having an opalescent quality characteristic of natural teeth and also having a sufficient chroma level. Such a dental mill blank may include: 40 mass % or more of an inorganic filler, the dental mill blank satisfying conditions (1) and (2): (1) a specimen with a thickness of 1.20±0.01 mm has a chromaticity satisfying −0.5≤a*.sub.black≤2.5 and 12.0≤b*.sub.black≤25.0 in the L*a*b* color system when measured against a black background; and (2) the specimen with a thickness of 1.20±0.01 mm has an opalescence value of 17.5 or more.

A method for creating a welded steel part includes providing a first steel plate having a first base, a first intermetallic alloy layer on the first base and a first metal alloy layer on the first intermetallic alloy layer; providing a second steel plate having a second base, a second intermetallic alloy layer on the second base and a second metal alloy layer on the second intermetallic alloy layer; butt welding the first and second steel plates at a weld so as to melt material from at least the first base, the first intermetallic alloy layer, the second base and the second intermetallic layer to form a molten weld material; austenizing the welded steel plates at a temperature between Ac1 and Ac3+100 degrees C. for a time greater than or equal to 20 seconds; and cooling the welded steel plates so as to render a uniform microstructure to the weld.

A method for manufacturing metal parts with split ends joined. An end of a metal plate or solid metal rod is split. The length of the incision is adjusted and a smooth split face is formed. A metal plate is secured by pinching both sides with a clamping device, or a solid metal rod is pinched on opposite portions on the periphery with a clamping device. The plate/rod is split longitudinally by slitting or cleaving the plate/rod by pressing a slitting or cleaving punch against the face of one end of the plate/rod. The splitting is advanced by repeating the operation of pressing the punch against the cleft of the splitting. In each splitting operation, the position of the clamping device is moved in advance of the next pressing by a stroke corresponding to the distance from one end of the plate/rod, to the distal end of a split-desired portion.

An extremely thin copper foil with a carrier is provided that can keep stable releasability even after being heated for a prolonged time at a high temperature of 350 C. or more. The extremely thin copper foil with a carrier includes a carrier composed of a glass or ceramic material; an intermediate layer provided on the carrier and composed of at least one metal selected from the group consisting of Cu, Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, In, Sn, Zn, Ga, and Mo; a release layer provided on the intermediate layer and including a carbon sublayer and a metal oxide sublayer or containing metal oxide and carbon; and an extremely thin copper layer provided on the release layer.

The present invention provides a zirconia pre-sintered body that develops the preferable shade with a short firing time. The present invention relates to a zirconia pre-sintered body comprising zirconia that comprises predominantly monoclinic, and a stabilizer capable of inhibiting a phase transformation of zirconia, the zirconia pre-sintered body satisfying the following conditions: L1, a1, b1, L2, a2, and b2 are confined within predetermined ranges, L1>L2, a1<a2, and b1<b2,
where (L1,a1,b1) represent values of (L*,a*,b*) of the L*a*b* color system after sintering as measured at a first point falling within an interval of a length from one end of the zirconia pre-sintered body to 25% of the entire length of a straight line extending along a first direction from one end to the other end of the zirconia pre-sintered body, and (L2,a2,b2) represent values of (L*,a*,b*) after sintering as measured at a second point falling within an interval of a length from the other end of the zirconia pre-sintered body to 25% of the entire length of the straight line, and the values of (L*,a*,b*) after sintering show unchanging patterns of increase and decrease in a direction from the first point to the second point.

A metal porous material in long sheet form that includes a frame having a three-dimensional network configuration. An end portion of the metal porous material in width direction has a burr with a length equal to or longer than 0.3 mm in a number equal to or less than 0.4 burrs/m.

The present invention accurately distinguishes a soldering material less likely to oxidize. A Cu core ball has a Cu ball having a predetermined size, and a solder layer coating the Cu ball. The Cu ball provides a space between a semiconductor package and a printed circuit board. The Cu core ball has the soldering material having lightness greater than or equal to 62.5 in L*a*b* color space subsequent to a heating storage test performed for 72 hours in a temperature-controlled bath at 150 C. with a temperature of 25 C. and 40% humidity, and the soldering material, prior to the heating storage test, having lightness greater than or equal to 65 in the L*a*b* color space and yellowness less than or equal to 7.0 in the L*a*b* color space.

The present invention relates to a dental prosthesis molding block (10) for producing a dental prosthesis part. The block comprises an inner material (13) that is at least partially surrounded by an outer material (14), the hardness of which differs from the hardness of the inner material (13). The inner material (13) forms part of a first surface (11) of the dental prosthesis molding block (10). The invention further relates to a method for producing a dental prosthesis part. In said method, a dental prosthesis molding block (10) is provided, and the dental prosthesis part is produced by removing material from the dental prosthesis molding block (10) using a CAD/CAM process. In doing so, a pin having a self-tapping external screw thread is created.