摘要:
The problem to be solved by the invention is to provide an epoxy resin composition for a prepreg, which is used in the manufacture of a printed circuit board containing a multilayer printed circuit board, wherein the epoxy resin composition for a prepreg is characterized by containing as essential components, a phosphorus compound that has 1.8 or more and less than 3 on average of a phenolic hydroxyl group that is reactive to an epoxy resin in the molecule, and that has 0.8 or more on average of a phosphorus element; a bifunctional epoxy resin that has 1.8 or more and less than 2.6 on average of epoxy groups in the molecule; a multi-functional epoxy resin that contains 2.8 or more on average of epoxy groups in one molecule; a hardening agent; an inorganic filler; and a molybdenum compound, wherein the epoxy resin composition for a prepreg is obtained by blending a pre-reacted epoxy resin, which is obtained by reacting at least the phosphorus compound with the bifunctional epoxy resin and the multi-functional epoxy resin, or the bifunctional epoxy resin only in advance, the bifunctional epoxy resin or the multi-functional epoxy resin, the hardening agent, the inorganic filler, and the molybdenum compound, which is excellent in flame retardance, heat resistance, thermal stiffness, and excellent in hole position accuracy without the production of a harmful substance at the time of combustion, a prepreg using the epoxy resin composition for a prepreg, and a multilayer printed circuit board using the prepreg.
摘要:
The problem to be solved by the invention is to provide an epoxy resin composition for a prepreg, which is used in the manufacture of a printed circuit board containing a multilayer printed circuit board, wherein the epoxy resin composition for a prepreg is characterized by containing as essential components, a phosphorus compound that has 1.8 or more and less than 3 on average of a phenolic hydroxyl group that is reactive to an epoxy resin in the molecule, and that has 0.8 or more on average of a phosphorus element; a bifunctional epoxy resin that has 1.8 or more and less than 2.6 on average of epoxy groups in the molecule; a multi-functional epoxy resin that contains 2.8 or more on average of epoxy groups in one molecule; a hardening agent; an inorganic filler; and a molybdenum compound, wherein the epoxy resin composition for a prepreg is obtained by blending a pre-reacted epoxy resin, which is obtained by reacting at least the phosphorus compound with the bifunctional epoxy resin and the multi-functional epoxy resin, or the bifunctional epoxy resin only in advance, the bifunctional epoxy resin or the multi-functional epoxy resin, the hardening agent, the inorganic filler, and the molybdenum compound, which is excellent in flame retardance, heat resistance, thermal stiffness, and excellent in hole position accuracy without the production of a harmful substance at the time of combustion, a prepreg using the epoxy resin composition for a prepreg, and a multilayer printed circuit board using the prepreg.
摘要:
A solid drawing material with which it is possible to smoothly and darkly draw on a smooth non-absorbing surface, as well as on conventional high-quality paper, drawing paper, or copy paper, and with which it is also possible to draw darkly and clearly on a transparent flat surface, and to easily erase a drawing on these non-absorbing surfaces using a fabric, paper, or whiteboard eraser. A solid drawing material containing at least a resin component, a wax component, a pigment, titanium dioxide, and a filler, wherein the resin component includes rosin and/or modified rosin in an amount that is within the range of 0.5 to 20 wt %, and the wax component includes a glycerin fatty acid ester and/or pentaerythritol fatty acid ester, both fatty acid esters having a melting point of 45° C. or higher, in an amount that is within the range of 8 to 50 wt %.
摘要:
A magnetic disk apparatus includes a rotation mechanism for driving a magnetic disk, a magnetic head slider being floated in close proximity to a surface of the magnetic disk, a recording/reproduction element for performing recording and playback of information, a drive unit for causing a distance between the record/reproduction element and the magnetic disk to change, and an arrangement to effect position determination of the magnetic head slider, wherein the apparatus has a detection unit for permitting the drive unit to gradually reduce the distance between the record/reproduction element and the magnetic disk and for detecting occurrence of contact therebetween, and a control unit for controlling the drive unit in such a way as to cause, the record/reproduction element to shift in position by a fixed amount to thereby let the distance between this element and magnetic disk increase accordingly.
摘要:
Concave grooves for forming a receiving layer for inkjet printing are provided at the inner peripheral and outer peripheral boundary portions of an application region on a disk substrate. The concave grooves are formed with a substantially V-shaped cross section, and with a depth d that is at least equal to the film thickness of the coating film within a central region between the concave grooves. A plurality of nozzles of a supply device is arrayed in a radial direction across the central region between the concave grooves, and a substantially constant quantity of coating liquid per unit of surface area is applied so as to form a coating film of a predetermined thickness. The applied coating liquid portions are flattened by a mutual leveling effect. During drying, the coating film inside the concave grooves does not dry first, but rather dries and contracts at substantially the same time as the coating film within the central region, meaning a receiving layer of uniform film thickness can be formed over the entire central region.
摘要:
A magnetic head slider, for sliding on a magnetic disk, which has a leading edge, a trailing edge, an air bearing surface having a front step bearing of submicron depth made from the leading edge, and a rail surface made from the front step bearing. A negative pressure recess which is deeper than the front step bearing, is formed as a recess from the rail surf ace, and a side step bearing with a depth identical to that of the front step bearing is made from the rail surface. Side padB are provided which each have a width W and length L, wherein W is greater than L.
摘要:
A magnetic head slider having a plurality of surfaces which are formed sequentially from an adjacent side to a magnetic disk, and a slider rail surface, which is arranged near an air flow-out edge on a nearest surface of the plurality of surfaces including a long sideways rail surface on an air flow-in side and a lengthwise rail surface on an air flow-out side, has a magnetic head. An area of the long sideways rail surface is larger than an area of the lengthwise rail surface.
摘要:
A pickup is moved in the radial direction of a partial CD-R, and the end position of a recorded area in the partial CD-R is detected based on a feature signal (on track signal) in the radial direction obtained during the movement. Information recorded in the recorded area is reproduced based on the detected end position, so that an accessing inability can be avoided, and the information in the recorded area can correctly be reproduced. Thus, information recorded in the partial CD-R can correctly be reproduced.
摘要:
A magnetic head slider has a magnetic head mounting surface holding a magnetic head, to be kept closest to a magnetic disk when the magnetic head slider is in operation, a slider rail surface contiguous with a surface, on the side of an air inlet end, and opposite sides of a portion, near an air outlet end, of the magnetic head and extending near to the air outlet end, a step bearing surface formed at least on the side of the air inlet end of the slider rail surface, and a negative-pressure groove formed so as to surround the step bearing surface. The magnetic head mounting surface is typically formed on an alumina protective film protecting the magnetic head. The variation of the flying height of the magnetic head slider with respect to a rolling direction is reduced and a proximity ability to approach the magnetic disk is improved.
摘要:
A recording apparatus, a recording method, and a recording medium, which allows a search operation based on a second segment information signal representing finely divided segments of a recording signal even in a player which can perform only a searching operation of a first segment information signal representing large segments of the recording signal. When a change of the second segment information signal of a signal to be recorded is detected, the first segment information signal being formed is updated and the first segment information signal is recorded together with an audio signal. That is, the second segment information signal of the signal to be recorded is converted into the first segment information signal and recorded together with the audio signal.