Composition for electrochemical device functional layer, functional layer for electrochemical device, laminate for electrochemical device, and electrochemical device

A functional layer for an electrochemical device, comprising:

• a non-conductive heat-resistant particle layer containing non-conductive heat-resistant particles;
• and a particulate polymer, wherein
• the particulate polymer is dispersed in the non-conductive heat-resistant particle layer,
• the particulate polymer has a particle diameter distribution value, expressed by Dv/Dn, of not less than 1.00 and less than 1.10, where Dv is a value for volume-average particle diameter of the particulate polymer and Dn is a value for number-average particle diameter of the particulate polymer, and
• a buried fraction of the particulate polymer in the non-conductive heat-resistant particle layer is 30% or less,
• wherein the buried fraction is a value that indicates a proportion of the number of particles of the particulate polymer that are buried in the non-conductive heat-resistant particle layer among 100 arbitrarily selected particles of the particulate polymer contained in the functional layer, and a particle of the particulate polymer is determined to be buried when the particle is completely buried in the non-conductive heat-resistant particle layer and does not have a section protruding from a surface of the non-conductive heat-resistant particle layer.