The present invention relates to a transparent polyimide film containing a polyimide and a phosphate ester. The content of the phosphate ester based on 100 parts by mass of the polyimide is 3 parts by mass or more, preferably 5 to 100 parts by mass. It is preferable to use a phosphate ester that has a high birefringence reduction effect and with which a decrease in the tensile modulus of the film is small. In production of the polyimide film, it is preferable to employ a method in which: a solvent-soluble polyimide resin and a phosphate ester are dissolved in an organic solvent exhibiting solubility with respect to the polyimide resin to prepare a polyimide solution; the polyimide solution is applied onto a substrate; and the organic solvent is removed.

A monomer represented by Chemical Formula 1: ##STR00001##
wherein, in Chemical Formula 1, R.sup.1, R.sup.2, A.sup.1, A.sup.2, L.sup.1, L.sup.2, o, p, q, and r are the same as defined in the detailed description.

A monomer represented by Chemical Formula 1: ##STR00001##
wherein, in Chemical Formula 1, R.sup.1, R.sup.2, A.sup.1, A.sup.2, L.sup.1, L.sup.2, o, p, q, and r are the same as defined in the detailed description.

An anhydride compound, polyimide, and thin film are provided. The anhydride compound has a chemical structure of

##STR00001##

wherein R.sup.1 is

##STR00002##

each of R.sup.4 is independently C.sub.1-6 alkylene group, m is an integer of 0 to 10, and m′ is an integer of 1 to 10; n is an integer of 1 to 10, each of R.sup.2 is independently hydrogen, saturated or unsaturated C.sub.1-6 hydrocarbon group, CF.sub.3, silanol group, silyl group, or Al(OH).sub.3; and R.sup.3 is

##STR00003##

silanol group, silyl group, or Al(OH).sub.3. The anhydride compound can be reacted with a diamine compound to form a polyimide.

The present invention relates to a method of insulating a motor, comprising: providing a impregnating resin; heating up the motor windings with electricity to 100-120° C., and potting the motor windings with the impregnating resin for 2-5 min at that temperature; heating up the motor windings with electricity to 140-160° C., and trickling the impregnating resin for 3-8 min for insulation; heating up the motor windings with electricity to 165-175° C., and curing for 15-45 min. The method of insulating a motor provided by the present invention has a higher resin filling level and a higher resin utilization rate, as well as faster curing speed.

A diamine monomer compound with reduced dielectric losses for better integrity and stability in digital transmissions is represented by a structural formula of

##STR00001##

wherein n.sub.1 is an integer greater than 1. A method for preparing the diamine monomer compound and a polyimide resin developed therefrom are disclosed. The diamine monomer compound introduces a long even numbered carbon chain and a liquid crystal unit structure, the long even numbered carbon chain giving flexibility, which reduces the regularity and rigidity of the molecular chain and facilitates film-forming processing. Dimensional stability is improved, and the coefficient of thermal expansion of the materials is reduced, the materials have good mechanical and heat-tolerant thermal properties, the loss factor and the coefficient of thermal expansion of the materials being reduced. A flexible film of the resin and an electronic device are also disclosed.

A diamine monomer compound with a structural formula of

##STR00001##

wherein n.sub.1 is an integer greater than 1, forms the basis of a dielectric material with reduced dielectric losses for improved signals transmission. A method for preparing the compound, a polyimide resin made from the compound, a flexible film, and an electronic device including the polyimide resin are also disclosed. The compound has a long but flexible even numbered carbon chain and a liquid crystal unit structure. The reduced regularity and rigidity of the molecular chain make the polyimide resin convenient for film-forming. Dimensional stability is improved, the coefficient of thermal expansion of the materials is reduced, and the materials have good mechanical and thermal properties, the electron loss factor and coefficient of thermal expansion of the materials being reduced.

A diamine monomer compound with a structural formula of

##STR00001##

wherein n.sub.1 is an integer greater than 1, forms the basis of a dielectric material with reduced dielectric losses for improved signals transmission. A method for preparing the compound, a polyimide resin made from the compound, a flexible film, and an electronic device including the polyimide resin are also disclosed. The compound has a long but flexible even numbered carbon chain and a liquid crystal unit structure. The reduced regularity and rigidity of the molecular chain make the polyimide resin convenient for film-forming. Dimensional stability is improved, the coefficient of thermal expansion of the materials is reduced, and the materials have good mechanical and thermal properties, the electron loss factor and coefficient of thermal expansion of the materials being reduced.

Provided are a solid electrolyte composition containing an inorganic solid electrolyte having a conductivity of an ion of a metal belonging to Group I or II of the periodic table and a binder having a specific hydrocarbon polymer segment and a specific segment, a solid electrolyte-containing sheet in which the same solid electrolyte composition is used and a manufacturing method therefor, an all-solid state secondary battery and a manufacturing method therefor, a polymer having a specific hydrocarbon polymer segment and a specific segment, and a non-aqueous solvent dispersion thereof.

Provided are a solid electrolyte composition containing an inorganic solid electrolyte having a conductivity of an ion of a metal belonging to Group I or II of the periodic table and a binder having a specific hydrocarbon polymer segment and a specific segment, a solid electrolyte-containing sheet in which the same solid electrolyte composition is used and a manufacturing method therefor, an all-solid state secondary battery and a manufacturing method therefor, a polymer having a specific hydrocarbon polymer segment and a specific segment, and a non-aqueous solvent dispersion thereof.