Laminated sheet

Abstract

A laminated sheet includes a sheet-shaped inductor including a plurality of wirings and a magnetic layer embedding the plurality of wirings, and a processing stability layer disposed on at least one surface in a thickness direction of the inductor. The magnetic layer includes a binder and a magnetic particle having a generally flat shape and whose material is a metal. The processing stability layer includes a cured product of a thermosetting resin composition. The thermosetting resin composition includes a thermosetting resin as an essential component. The thermosetting resin composition includes at least one kind of particle, as an optical component, selected from the group consisting of a first particle having a generally spherical shape and a second particle having a generally flat shape and whose material is an inorganic compound.

1 . A laminated sheet comprising:
 a sheet-shaped inductor including a plurality of wirings and a magnetic layer embedding the plurality of wirings, and   a processing stability layer disposed on the inductor, wherein   the magnetic layer has a first surface and a second surface spaced from the first surface,   the magnetic layer includes a binder, and   a magnetic particle having a generally flat shape and whose material is a metal;   the processing stability layer includes a cured product of a thermosetting resin composition; and   the thermosetting resin composition includes:   a thermosetting resin, and   at least one particle selected from the group consisting of a first particle having a generally spherical shape and a second particle having a generally flat shape and whose material is an inorganic compound, and any combinations thereof; and   wherein the processing stability layer is in contact with the first surface of the magnetic layer.   
     
     
         2 . The laminated sheet according to  claim 1 , wherein
 the processing stability layer is in contact with the entire first surface.   
     
     
         3 . The laminated sheet according to  claim 1 , further comprising a second processing stability layer being contact with the second surface of the magnetic layer. 
     
     
         4 . The laminated sheet according to  claim 3 , wherein
 the second processing stability layer is in contact with the entire second surface.   
     
     
         5 . The laminated sheet according to  claim 1 , wherein
 the particle included in the thermosetting resin composition consists of the first particle.   
     
     
         6 . The laminated sheet according to  claim 1  satisfying at least one test of the following test (a) to test (e):
 test (a): the laminated sheet is trimmed into a 3 cm square piece to fabricate a sample, and the relative permeability μ1 thereof at a frequency of 10 MHz is determined, thereafter, the sample is immersed in 200 mL of copper sulfate plating solution containing 66 g/L of copper sulfate pentahydrate, 180 g/L of sulfuric acid concentration, 50 ppm of chlorine, and Top Lutina alpha at 25° C. for 120 minutes, and thereafter, the relative permeability μ2 of the sample at a frequency of 10 MHz is determined, by the following formula, a rate of change of the magnetic permeability before and after the immersion is determined, and as a result, the rate of change of the magnetic permeability of the sample is 5% or less:
   Rate of Change of Magnetic Permeability (%)= Iμ 1−μ2 I/μ 1×100;
 
 
 test (b): the laminated sheet is trimmed into a 3 cm square piece to fabricate a sample, and the relative permeability μ3 thereof at a frequency of 10 MHz is determined, thereafter, the sample is immersed in 200 mL of an acid active aqueous solution containing 55 g/L of sulfuric acid at 25° C. for 1 minute, and thereafter, the relative permeability μ4 of the sample at a frequency of 10 MHz is determined, by the following formula, a rate of change of the magnetic permeability before and after the immersion is determined, and as a result, the rate of change of the magnetic permeability of the sample is 5% or less:
   Rate of Change of Magnetic Permeability (%)= Iμ 3−μ4 I/μ 3×100;
 
 
 test (c): the laminated sheet is trimmed into a 3 cm square piece to fabricate a sample, and the relative permeability μ5 thereof at a frequency of 10 MHz is determined, thereafter, the sample is immersed in 200 mL of Reduction Solution Securiganth P manufactured by Atotech Japan K.K. at 45° C. for 5 minutes, and thereafter, the relative permeability μ6 of the sample at a frequency of 10 MHz is determined, by the following formula, a rate of change of the magnetic permeability before and after the immersion is determined, and as a result, the rate of change of the magnetic permeability of the sample is 5% or less:
   Rate of Change of Magnetic Permeability (%)= Iμ 5−μ6 I/μ 5×100;
 
 
 test (d): the laminated sheet is trimmed into a 3 cm square piece to fabricate a sample, and the relative permeability μ7 thereof at a frequency of 10 MHz is determined, thereafter, the sample is immersed in 200 mL of Concentrate Compact CP manufactured by Atotech Japan K.K. at 80° C. for 15 minutes, and thereafter, the relative permeability μ8 of the sample at a frequency of 10 MHz is determined, by the following formula, a rate of change of the magnetic permeability before and after the immersion is determined, and as a result, the rate of change of the magnetic permeability of the sample is 5% or less:
   Rate of Change of Magnetic Permeability (%)= Iμ 7−μ8 I/μ 7×100;
 
 
 test (e): the laminated sheet is trimmed into a 3 cm square piece to fabricate a sample, and the relative permeability μ9 thereof at a frequency of 10 MHz is determined, thereafter, the sample is immersed in 200 mL of Swelling Dip Securiganth P manufactured by Atotech Japan K.K. at 60° C. for 5 minutes, and thereafter, the relative permeability μ10 of the sample at a frequency of 10 MHz is determined, by the following formula, a rate of change of the magnetic permeability before and after the immersion is determined, and as a result, the rate of change of the magnetic permeability of the sample is 5% or less:
   Rate of Change of Magnetic Permeability (%)= Iμ 9−μ101/μ9×100.
 
 
 
     
     
         7 . The laminated sheet according to  claim 1 , wherein
 the arithmetic average roughness Ra of a surface of the processing stability layer is 10 μm or less.