Mitsubishi Gas Chemical Company, Inc.

Takuya Hasaki

Shinya Komatsu

Yousuke Matsuyama

Reiki Akita

Nobuyuki Ikeguchi

Toshihiko Kobayashi

Masahiko Ishikawa

Atsushi Hirashima

Katsushige Hayashi

Shigeru Horie

Mitsuhiko Masumoto

Norio Nagai

Takayuki Kamei

Masayuki Nakajima

Noritsugu Umehara

Mitsuo Ejiri

Noriaki Sugimoto

Katsutoshi Ihara

Takayuki Tokoroyama

The present invention provides an entry sheet for drilling excellent in hole position accuracy compared with the conventional entry sheet for drilling. Such an entry sheet for drilling is an entry sheet for drilling comprising metallic support foil and a layer comprising a resin composition formed on at least one surface of the metallic support foil, in which the resin composition contains a resin and 70 parts by mass to 130 parts by mass of molybdenum disulfide based on 100 parts by mass of the resin, and the layer comprising the resin composition has a thickness in a range from 0.02 to 0.3 mm.

Entry sheet for drilling

A process for the production of an entry sheet for drilling a printed wiring board material, which process comprises forming a multi-layered water-soluble resin composition layer on at least one surface of a metal foil, wherein an aqueous solution of a water-soluble resin composition is applied to the metal foil, dried and solidified to form one water-soluble resin composition layer, the application, drying and solidification of the aqueous solution of the water-soluble resin composition are repeated at least once to form at least one water-soluble resin composition layer on the above one water-soluble resin composition layer, the multi-layered water-soluble resin composition layer is composed of these water-soluble resin composition layers, the multi-layered water-soluble resin composition layer has a thickness of at least 50 &#x3bc;m and is almost free from air bubbles, and an entry sheet for drilling a printed wiring board material obtained by the above process.

Process for the production of entry sheet for drilling and entry sheet

Provided is an entry sheet for drilling that, compared with a conventional entry sheet for drilling, has better hole position accuracy, can suppress drill bit breakage, and exhibits less processing chips wrapping around the drill bit. This entry sheet for drilling includes a metallic support foil and a layer comprising a resin composition that is formed on at least one surface of the metallic support foil, wherein the resin composition contains a cellulose derivative (A) and a water-soluble resin (B), the cellulose derivative (A) includes a hydroxyalkyl cellulose and/or a carboxyalkyl cellulose having a weight average molecular weight of 20,000 to 350,000, and based on 100 parts by mass of the resin composition, the content of the cellulose derivative (A) is 5 to 40 parts by mass and the content of the water-soluble resin (B) is 60 to 95 parts by mass.

Entry sheet for drilling and drilling method

A lubricant sheet suitable for use in a process of drilling a laminate or a plastic board, comprising a metal foil or an organic film, and a lubricant resin composition layer or a primer layer and the lubricant resin composition layer, the lubricant resin composition layer or the primer layer and the lubricant resin composition layer being formed on at least one surface of the metal foil or the organic film, wherein at least one layer of the primer layer and the lubricant resin composition layer contains a colorant, and a drilling method using the above lubricant sheet.

Lubricant sheet for drilling and method of drilling

There are provided a process for the production of an entry sheet for drilling, comprising preparing a water-soluble resin composition solution by using a mixed solvent containing water and isopropyl alcohol in a specific ratio as a solvent of a water-soluble resin composition, then applying the solution to a sheet-like base material and drying the resultant base material to form a resin layer on the base material, and a method of drilling a printed wiring board material using the above entry sheet. According to the present invention, the problems of remaining bubbles in the resin layer and a decrease in surface flatness and smoothness due to the occurrence of a ridge, which are caused because the melting point of the water-soluble resin is lower than the boiling point of water, are overcome, and an entry sheet for drilling excellent in hole position accuracy is provided.

Process for the production of entry sheet for drilling and use thereof

An entry sheet for drilling for a printed wiring board material, which comprises a water-soluble resin (A) and a water-insoluble lubricant (B) as essential components,

Entry sheet for drilling and method for drilling hole

A process for preparing a polycarbonate which comprises performing a transesterification and a polycondensation reaction with a diarylcarbonate and dihydroxyaryl compound, in a reaction apparatus composed of stainless steel comprising at least 12% by weight of Ni, and at least 22% by weight of Cr, and having Fe as the remaining main component. A polycarbonate which has a good color, is stable to hydrolysis and resistant to heat-yellowing is the resulting product.

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Tokyo, Japan

Takuya Hasaki