An object of the present invention is to provide a liquid crystal polymer film having an excellent peel strength of a laminate produced by sticking a metal foil to the liquid crystal polymer film; and a laminate.

A liquid crystal polymer film including a liquid crystal polymer, in which in a case where a cross-section of the liquid crystal polymer film along a thickness direction of the liquid crystal polymer film is exposed and immersed in monomethylamine, and then void regions are extracted from an observed image of a cross-section obtained by using an electron microscope, an average value of widths of the void regions is 0.01 to 0.1 μm and an area ratio of the void regions in the observed image of the cross-section is 20% or less.

An object of the present invention is to provide a polymer film having a low dielectric loss tangent and a small difference in a linear expansion coefficient from that of a copper foil; and a laminate.

The polymer film of an embodiment of the present invention is a polymer film including a liquid crystal polymer, in which a hardness A at a distance of half of a thickness of the polymer film and a hardness B at a distance of 1/10 of the thickness of the polymer film satisfy a relationship of Expression (1A), and in a case where positions at distances of 1/10, 4/10, and 6/10 of the thickness of the polymer film are defined as a position T1, a position T2, and a position T3, respectively; and a region from the one surface to the position T1 is defined as a first surface layer region, and a region from the position T2 to the position T3 is defined as a central region, a void area proportion X in the first surface layer region and a void area proportion Y in the central region satisfy a relationship of Expression (2A).

[00001]$\left(\text{Hardness A + Hardness B}\right)/2\ge 0.10\text{GPa}$

[00002]$\text{Void area proportion Y - Void area proportion X}\ge \text{0}\text{.10\%}$

Provided are a film including a matrix material, and a particle having an elastic modulus at 25° C. which is higher than an elastic modulus of the matrix material, in which the film has a region A at at least a part between the matrix material and the particle, and the region A contains a compound having a loss tangent of 0.1 or greater at 25° C.; and a laminate formed of the film.

A metal-clad laminate includes: an insulating layer; and a metal foil being in contact with at least one surface of the insulating layer. The insulating layer contains a cured product of a resin composition containing a polyphenylene ether copolymer having an intrinsic viscosity of 0.03 to 0.12 dl/g measured in methylene chloride at 25° C. and having an average of 1.5 to 3 specific groups per molecule at its molecular terminal, a thermosetting curing agent having two or more carbon-carbon unsaturated double bonds at its molecular terminal, and a thermoplastic elastomer. The metal foil includes a metal substrate, and a cobalt-containing barrier layer provided on at least a contact surface of the metal substrate, the contact surface being in contact with the insulating layer. The contact surface has a ten-point average roughness Rz of 2 μm or less as a surface roughness.

A method of bonding layers of dielectric materials includes providing a surface one of the layers with microscale- and/or nanoscale-size bonding elements forming contact points of the layers and bringing a layer of the layers into a mutual position according to an intended use. The method also includes illuminating the layer whose surface is provided with bonding elements by an incident electromagnetic wave, the propagation direction of which is substantially orthogonal to the one of the layers, and whose wavelength is selected depending on an absorption spectrum of a material forming the one of the layers and generating condensed optical beams within said bonding elements or close to a tip of said bonding elements intended to be in contact with the other layer. The method further includes heating and melting the bonding elements by high-intensity focal spots formed by said generated optical beams and maintaining the layers into a mutual position until and bonding of the layers.

An antenna packaged substrate includes: a substrate, a first antenna radiating patch disposed on a surface of the substrate, a second antenna radiating patch disposed over the first antenna radiating patch, and a dielectric stack disposed between the first antenna radiating patch and the second antenna radiating patch. The dielectric stack includes a first dielectric layer, a bonding layer disposed on a side that is of the first dielectric layer and faces the first antenna radiating patch, and a second dielectric layer disposed on a side that is of the first dielectric layer and faces the second antenna radiating patch. A dielectric constant of the first dielectric layer is lower than a dielectric constant of the substrate, and an expansion coefficient of the second dielectric layer is lower than an expansion coefficient of the first dielectric layer.

An adhesive sheet comprising at least a pressure sensitive adhesive layer, wherein the adhesive sheet has an adhesive strength to soda-lime glass of larger than 1 N/25 mm and 100 N/25 mm or less, a pressure sensitive adhesive that constitutes the pressure sensitive adhesive layer is formed of a pressure sensitive adhesive composition that contains a (meth)acrylic ester polymer (A), and the (meth)acrylic ester polymer (A) contains, as a monomer unit that constitutes the polymer, an ethylene carbonate-containing monomer having an ethylene carbonate structure represented by Formula (1) below.

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Provided are a thermosetting resin composition, and a prepreg, a laminate and a printed circuit board using same. The thermosetting resin composition comprises a resin component comprising a modified cycloolefin copolymer and other unsaturated resins. The modified cycloolefin copolymer is a reaction product of maleic anhydride and a cycloolefin copolymer; the cycloolefin copolymer is a copolymerization product of a monomer A and a monomer B; the monomer A is selected from one of or a combination of at least two of norbornene, cyclopentadiene, dicyclopentadiene, tricyclopentadiene, and (I); and the monomer B is selected from one of or a combination of at least two of C2-C3 olefins and C2-C3 alkynes. The laminate prepared by using the provided thermosetting resin composition has good dielectric properties, peel strength and thermal resistance, and can satisfy the current requirements of properties for printed circuit board substrates in the field of high-frequency and high-speed communications.

A polyhydric phenol resin is provided. The polyhydric phenol resin comprises a polyhydric phenol resin component and a first component. When the polyhydric phenol resin is characterized in a high-performance liquid chromatography (HPLC), the first component is eluted at a retention time ranging from 27.1 minutes to 28.0 minutes, and based on the total area of the chromatographic peaks of the polyhydric phenol resin, the area percentage of the chromatographic peak of the first component at the corresponding retention time in the spectrum ranges from 1.0% to 20%.

An object of the present invention is to provide a polymer film, in which in a case where a laminate is manufactured by sticking a metal foil to the polymer film, the adhesiveness between the polymer film and the metal foil is excellent, and the performance of suppressing a misregistration of a wiring line formed on the metal foil is excellent even in a case of further laminating a sticking material on the wiring line; and a laminate.

A polymer film including a liquid crystal polymer, in which in a case where an elastic modulus at a position A at a distance of half of a thickness of the polymer film from one surface toward the other surface of the polymer film is defined as an elastic modulus A and an elastic modulus at a position B at a distance of ⅛ of the thickness of the polymer film from one surface toward the other surface of the polymer film is defined as an elastic modulus B in a cross-section along a thickness direction of the polymer film, a ratio B/A of the elastic modulus B to the elastic modulus A is 0.99 or less and the elastic modulus A is 4.0 GPa or more.