Abstract: A pipe for a cooling unit comprises an outer pipe, and an inner pipe shorter than the outer pipe and located at an evaporating portion in the outer pipe, a circulation gap being defined between the inner wall surface of the outer pipe and the outer wall surface of the inner pipe and leading from one end to the other end of the inner pipe, whereby working liquid is permitted to boil up continuously and stably in the evaporating portion even uder a low temperature flow of working liquid.

Abstract: A process for synthesizing an N,N-disubstituted hydrazone comprises carrying out nitrozation by adding an aqueous solution of sodium nitrite to a solution having one part by weight of an N,N-disubstituted amine dissolved in 3 to 30 parts by weight of an organic acid, then reducing the nitrozated product to an N,N-disubstituted hydrazine by adding a reducing agent to the mixture containing the nitrozated product, and thereafter adding to the mixture containing the N,N-disubstituted hydrazine a carbonyl compound of the formula: ##STR1## wherein A represents an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent, B represents a hydrogen atom, an alkyl group, an aryl group or an aromatic heterocyclic group, which may have a substituent, thereby performing condensation of the N,N-disubstituted hydrazine with the carbonyl compound.

Abstract: An electrophotographic photosensitive member comprises a conductive support, and a photosensitive layer containing as azo pigment as a charge-generating material, wherein in a powder X-ray diffraction pattern of the azo pigment contained in said photosensitive layer the ratio (X) of the diffracted beam intensity at a maximum peak at 2.theta. of from 5.degree. to 20.degree. to the X-ray intensity at the background is 0.8 or more, provided that:X=(P-B)/B,whereinP: X-ray intensity at a peak position at the maximum peak; andB: X-ray intensity at a peak position on the line connecting the bottoms at the both sides of the maximum peak.

Abstract: An electrophotographic photosensitive member comprises at least a charge generation layer and a charge transport layer on an electroconductive substrate, wherein said charge generation layer contains, as a binder, a polyvinylacetal resin obtained by acetalization reaction of polyvinyl alcohol and aldehyde compound represented by the following general formula:Ar-CHOwherein Ar stands for a substituted or unsubstituted aryl radical.

Abstract: An improved electrophotographic photosensitive member is composed of a layer containing a hydrazone compound represented by the formula ##STR1## wherein R.sub.2 and R.sub.3 are each unsubstituted alkyl or substituted alkyl, unsubstituted aralkyl or substituted aralkyl, or unsubstituted aryl or substituted aryl, with the proviso that R.sub.2 and R.sub.3 are not simultaneously alkyls, n is 1 or 2, when n is 1, A represents ##STR2## wherein R.sub.1 is C.sub.1 -C.sub.5 alkyl, unsubstituted aralkyl, or substituted aralkyl, and when n is 2, A represents a direct single bond between two ##STR3## radicals.

Abstract: An organic film comprising at least one compound of the following formulae (1)-(5): ##STR1## wherein R.sub.11 and R.sub.13 each represent substituted or unsubstituted aryl, R.sub.12 represents substituted or unsubstituted arylene, and A.sup..crclbar. represents an anionic residue; ##STR2## wherein R.sub.21, R.sub.22, and R.sub.24 each represent substituted or unsubstituted aryl, R.sub.23 represents substituted or unsubstituted arylene, and A.sup..crclbar. represents an anionic residue; ##STR3## wherein R.sub.31, R.sub.33, and R.sub.35 each represent substituted or unsubstituted aryl, R.sub.32 and R.sub.34 each represent substituted or unsubstituted arylene, and A.sup..crclbar. represents an anionic residue; ##STR4## wherein R.sub.41 represents alkyl, substituted or unsubstituted phenyl, or substituted or unsubstituted styryl, R.sub.42 represents substituted or unsubstituted arylene, R.sub.43 represents substituted or unsubstituted aryl, and A.sup..crclbar.

Abstract: An electrophotographic photosensitive member comprises a layer containing a binder and at least one hydrazone compound represented by the following formula (1), (2), (3), (4), or (5): ##STR1##

Abstract: An electrophotographic photosensitive member is characterized by having a layer which contains at least one hydrazone compound represented by the following formula (1) or (2): ##STR1## wherein R.sub.11 represents substituted or unsubstituted naphthyl; R.sub.12 represents substituted or unsubstituted alkyl, substituted or unsubstituted aralkyl, or substituted or unsubstituted aryl; R.sub.13 represents hydrogen, alkyl, or alkoxy; R.sub.14 and R.sub.15 each represent substituted or unsubstituted alkyl, substituted or unsubstituted aralkyl, or substituted or unsubstituted aryl; n is 0 or 1; when n=1, R.sub.14 and R.sub.15, together with the nitrogen which links them, may complete a cyclic amino group; X represents a group necessary for completing a benzene ring or naphthalene ring; R.sub.21 and R.sub.22 each represent hydrogen, halogen, alkyl, alkoxy or disalkylamino; and R.sub.23, R.sub.24, R.sub.25, R.sub.26 and R.sub.

Abstract: An electrophotographic photosensitive member is characterized by having a layer containing at least one of hydrazone group compounds represented by the following formula (1) or of ketazine group compounds represented by the following formula (2): ##STR1## In the formula, R.sub.11 and R.sub.12 independently of one another represent hydrogen, substituted or unsubstituted aryl, or substituted or unsubstituted heterocyclic radical; R.sub.13 and R.sub.14 independently of one another represent subsituted or unsubstituted alkyl, substituted or unsubstituted aralkyl, substituted or unsubstituted aryl, or substituted or unsubstituted heterocyclic radical; and R.sub.15 represents a divalent organic residue. ##STR2## In the formula, R.sub.21, R.sub.22, R.sub.23, and R.sub.24 independently one another represent substituted or unsubstituted alkyl, substituted or substituted aralkyl, or substituted or unsubstituted aryl, or R.sub.21 and R.sub.

Abstract: An electrophotographic photosensitive member having a layer containing at least one compound represented by the formula ##STR1## wherein X.sub.1 represents a residue necessary for completing a substituted or unsubstituted aromatic hydrocarbon ring; X.sub.2 represents a residue necessary for completing a substituted or unsubstituted heterocyclic ring; R.sub.1, R.sub.2, R.sub.3, and A each represent hydrogen, alkyl, aralkyl, or aryl, substituted or unsubstituted; and m is 0 or 1.

Abstract: An electrophotographic photosensitive member is characterized by having a layer containing at least one hydrazone compound represented by the following formula [I] or [II]: ##STR1## wherein R.sub.11 and R.sub.12 represent hydrogen, halogen, substituted or unsubstituted alkyl, alkoxy, substituted or unsubstituted aryloxy, or substituted amino, provided that at least one of R.sub.11 and R.sub.12 is substituted amino or alkoxy; R.sub.13 and R.sub.14 represent substituted or unsubstituted alkyl or substituted or unsubstituted aryl, provided that at least one of R.sub.13 and R.sub.14 is substituted or unsubstituted aryl, or R.sub.13 and R.sub.14, together with the nitrogen atom which links them, represent a nitrogen-containing heterocyclic ring; R.sub.15, R.sub.16, R.sub.17, and R.sub.18 represent hydrogen, halogen, substituted or unsubstituted alkyl, alkoxy, substituted or unsubstituted aryloxy, or substituted amino; m and n represent 0 or 1; R.sub.21 and R.sub.

Abstract: An electrophotographic photosensitive member comprises a layer containing at least one member of the hydrazone compounds of the formula: ##STR1## where R.sub.1, R.sub.2 and R.sub.3 are selected from the group consisting of substituted or unsubstituted alkyl, substituted or unsubstituted aralkyl, and substituted or unsubstituted aryl, and R.sub.1 and R.sub.2 can not be simultaneously alkyl; and R.sub.4 is substituted or unsubstituted aryl.