Patent ID: 11924968
Assignee: MURATA MANUFACTURING CO., LTD.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC C  H  B | IPC B  H

Claim 0:
1. A laminate comprising multiple glass ceramic layers each containing quartz and a glass, wherein the glass contains SiO2, B2O3, Al2O3, and M2O, and wherein M2O is at least one selected from the group consisting of Li2O, Na2O, and K2O,
wherein the laminate comprises an upper surface layer portion, a lower surface layer portion, and an inner layer portion sandwiched between the upper surface layer portion and the lower surface layer portion, and the inner layer portion comprises a plurality of layers laminated together,
an Al2O3 content of the upper and lower surface layer portions being higher than an Al2O3 content of the inner layer portion, and a M2O content of the upper and lower surface layer portions being lower than a M2O content of the inner layer portion,
each of the upper and lower surface layer portions having a thickness of 2 μm or greater and 6 μm or smaller.