Abstract: A thermosensitive recording material comprising (a) a support, and (b) a thermosensitive recording layer formed on the support, comprising a leuco dye and a color developing agent comprising a metal salt or metal complex of a compound having formula (I), which is capable of inducing color formation in the leuco dye upon application of heat thereto: ##STR1## wherein X represents a halogen, an alkyl group having 1 to 10 carbon atoms, or an alkoxyl group having 1 to 10 carbon atoms; R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 independently represent hydrogen, a halogen, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxyl group having 1 to 10 carbon atoms, an aralkyloxyl group having 7 to 20 carbon atoms, an aryloxyl group having 6 to 20 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aralkylthio group having 6 to 20 carbon atoms or an arylthio group having 6 to 20 carbon atoms, R.sup.1 and R.sup.2, or R.sup.2 and R.sup.

Abstract: Disclosed is a heat-sensitive recording material comprising an aromatic isocyanate compound, an imino compound which reacts with said aromatic isocyanate compound upon application of heat to form color, and a support, wherein a coating color comprising a dispersion obtained by pulverizing a mixture of said aromatic isocyanate compound and an alcoholic compound has been coated on the support. This heat-sensitive recording material is excellent in image stability and sensitivity.

Abstract: Disclosed is a developer sheet useful in forming reproductions having a glossy finish, or in forming transparencies comprising:a support having a layer of a finely divided, thermoplastic, developer material on the surface thereof, said developer material being capable of reacting with a color precursor to produce a visible image and being capable of coalescing into a thin film which imparts gloss to said image upon application of heat and/or pressure, and having a surfactant admixed within said layer of developer material to aid in the coalescing of said developer material into a thin film.

Abstract: Pressure-sensitive reactive recording material containinga) as the color-forming agent, a tetraindolylheptamethine ether or alcohol of the formulae I/1, I/2, I/3 or I/4 ##STR1## b) and, as the color developer, the salt of a polyvalent metal and an aromatic carboxylic acid having at least 10 carbon atoms, of the formula (II) ##STR2## wherein A, B, D and E denote ##STR3## and the other radicals have the meanings given in the description, produces light-stable copies which can also be read by machines (OCR).

Abstract: A pressure-sensitive or heat-sensitive recording material in which the color reactant system contains, as main components(A) a polycyclic compound of the formula ##STR1## in which X is a monocyclic or polycyclic aromatic or heteroaromatic radical,Y is a substituent detachable as an anion,Q.sub.1 is --O--, --S--, >N--R or >N--NH--R,Q.sub.2 is --CH.sub.2 --, --CO--, --CS-- or --SO.sub.2 -- andR is hydrogen, C.sub.1 -C.sub.12 alkyl, C.sub.5 -C.sub.10 cycloalkyl, aryl such as phenyl or aralkyl such as benzyl, and ring A is an aromatic or heterocyclic radical having 6 ring atoms, which can have an aromatic fused ring, it being possible for both ring A and the fused ring to be substituted,(B) an organic condensation component capable of forming a chromogenic compound with component (A) and(C) an electron-withdrawing and a color-developing component.

Abstract: A heat sensitive recording material comprising a substrate and a recording layer thereon incorporating a colorless or light-colored basic dye and a color acceptor reactive with the dye to form a color when contacted therewith, the recording material being characterized in that, as the color acceptor is used at least one compound selected from the group consisting of 4-hydroxy-4'-isopropyloxydiphenylsulfone, 4,4'-(1,3-dimethylbutylidene) bisphenol, 4,4'-(1-phenylethylidene)bisphenol, 4,4'-(p-phenylenediisopropylidene)bisphenol and 4,4'-(m-phenylenediisopropylidene) bisphenol, and to the recording layer is added at least one of a heat-fusible substance represented by the formula [I] ##STR1## wherein X is hydrogen atom, halogen atom, C.sub.1.about.4 alkyl or C.sub.1.about.4 alkoxy.

Abstract: Fluoran compounds represented by the general formula (I) ##STR1## (where R is an alkyl group having 9 to 12 carbon atoms) and coloring recording materials containing the said compounds as coloring components, and benzoic acid derivatives represented by the general formula (II) ##STR2## (where R is an alkyl group having 9 to 12 carbon atoms).

Abstract: Pressure-sensitive or heat-sensitive recording material in which the color reactant system contains, as essential components,(A) an electron-donating compound of the formula ##STR1## in which Y.sub.1 and Y.sub.2 are substituents which are detachable as anions and can be identical, different or bound to one another and Q.sub.1 is --O--, --S--, >N--R or >N--NH--R,Q.sub.2 is --CH.sub.2 --, --CO--, --CS-- or SO.sub.2 --,R is hydrogen, C.sub.1 -C.sub.12 alkyl, C.sub.5 -C.sub.10 cycloalkyl, aryl or aralkyl and ring A is an aromatic radical which has 6 ring atoms and can contain an aromatic fused ring, it being possible not only for ring A but also for the fused ring to be substituted,(B) two organic condensation components which are identical to or different from one another and together are capable of forming a chromogenic compound with component (A) and(C) an electron-withdrawing and color-developing component.

Abstract: In situ dye generation in a thermal transfer system is achieved by reacting an electrophile with a coupler compound to form an arylidene dye. The electrophile and/or the coupler compound are transferred from a donor element to a receiver element where they react to form a colored dye. The invention comprises a dye image recording element comprising a support bearing the electrophile which has the structure: ##STR1## wherein X is halogen, substituted or unsubstituted alkylsulfonyloxy, substituted or unsubstituted arylsulfonyloxy, or substituted or unsubstituted acyloxy;E.sup.1, E.sup.2, E.sup.3, and E.sup.4 are each independently hydrogen, substituted or unsubstituted alkyl or alkenyl having up to about six carbon atoms, substituted or unsubstituted aryl having up to about ten carbon atoms, halogen, cyano, benzoxazolyl, nitro, --CO.sub.2 R, --COR, --CONH.sub.2, --CONHR, --CONRR, or --SO.sub.

Abstract: Leuco dyes of the formula (I) are disclosed, ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each represent an alkyl group having 1 to 10 carbon atoms; X represents hydrogen, an alkyl group having 1 to 10 carbon atoms, an alkoxyl group having 1 to 10 carbon atoms or a halogen; and Y represents R.sub.5 --Z--SO.sub.2 NH--, R.sub.6 --Z--CONH--, or ##STR2## in which Z represents ##STR3## R.sub.5 and R.sub.6 each represent hydrogen, an alkyl group having 1 to 10 carbon atoms, or a halogen; and R.sub.7 and R.sub.8 each represent hydrogen, provided that both R.sub.7 and R.sub.8 may not be hydrogen, a cyano group, or --COR.sub.9, in which R.sub.9 represents a lower alkyl group, a lower alkoxyl group, a phenyl group which may be substituted by an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, or a halogen; a naphthyl group which may be substituted by an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms or a halogen.

Abstract: A heat-sensitive recording material comprising a dye precursor which is colorless or light-colored in the usual state and a color developing agent capable of reacting with said dye precursor upon heating to develop a color which is a combination of compounds of the following chemical formulas (I) and (II).

Abstract: A heat sensitive recording material which is comprised of a support having thereon at least a transparent heat sensitive layer excellent in freshness-keeping property is disclosed. The transparent heat sensitive layer is obtained by coating a solution obtained by mixing a microcapsule containing a colorless or light colored electron donating dye precursor with an emulsion prepared by dispersing a color developer dissolved in an organic solvent, which is slightly soluble or insoluble in water, into an aqueous solution containing both of a surface active agent and water soluble polymer. The stabilities of emulsion and heat sensitive layer are improved by using a partially saponified polyvinyl alcohol as the water soluble polymer and/or adding a metal salts of a salicylic acid derivatives into the coolor developer. A heat sensitivity of the heat sensitive recording material is improved by using a organic solvent having a boiling point lower than 150.degree. C.

Abstract: The present invention provides an intensely colored thermographic medium useful for bar-coding applications which utilize near infrared scanning systems. The medium is formed of a substrate having on at least one surface thereof a coating comprising: a transparent film-forming binder, an organic solvent soluble catechol, a metal salt and colorant.

Abstract: A recording material wherein a color forming system comprising (a) a fluorene compound as a dye precursor, (b) a color developer, (c) an isocyanate compound, and (d) in imido compound, gives a developed color image having an absorption at near infrared portion and excellent image storability.

Abstract: There is disclosed a thermosensitive recording material comprising an ordinarily colorless or slightly colored dye precursor, an electron receptive compound (developer) coloring said dye precursor by reacting when heated, and a compound of following general formula (I) ##STR1## wherein R.sub.1 and R.sub.2 each represents hydrogen atom, alkyl, alkenyl or aryl group, and R.sub.1 and R.sub.2 may be different from each other; may also be linked together to form cycloalkyl, cycloether, and the like; and R.sub.3 and R.sub.4 each represents hydrogen atom, alkyl, alkenyl, alkoxy or aryl group and halogen atom, and R.sub.3 and R.sub.4 may be different from each other.

Abstract: A heat sensitive recording material having a support and a color-developing layer which comprises both as a colorless basic chromogenic dye at least one of a particular fluorane-type leuco dye and a particular divinyl compound, the heat-sensitive recording material of this invention having superior thermal responsibility, light resistance, weather resistance, oil resistance and optical readability in the near infrared region.

Abstract: A composition for use in a thermal-sensitive paper coating and a heat-sensitive recording material utilizing the coating, which composition comprises a phenolic developer, e.g., a traditional low speed phenolic having a melting point greater than 120.degree. C., and a pseudo developer. The pseudo developer is combined with the phenolic developer in an amount effective to provide for the formation of homogenous phase when the composition is melted, which phase further solidifies back to a single crystalline phase when cooled.

Abstract: This invention relates to a thermal printing material comprising a substrate and a thermal printing layer formed thereon containing an aromaticity-possessing isocyanate compound, an imino compound having at least one>C.dbd.NH group which reacts with said aromaticity-possessing isocyanate compound on heating to produce color, and one or more aniline derivatives having at least one amino group, said thermal printing layer being intended to improve the image storage properties, in particular, the storage properties of color-undeveloped portion (ground), and it can be utilized in recorders for measurements, facsimiles, printers, terminals of computers, labels, and automatic ticket vending machines.

Abstract: A heat-sensitive recording material is disclosed. The material comprises a support having provided on the same surface thereof microcapsules containing a basic colorless dye and an organic solvent, and a developer capable of reacting with the basic colorless dye to develop a color, the capsule walls of said microcapsules being impermeable to either of the basic colorless dye and the developer at room temperature but becoming permeable to the colorless dye and/or the developer upon application of heat. The organic solvent is a compound containing at least two benzene rings in the molecule thereof with a total number of at least one hetero atom selected from nitrogen, sulfur, oxygen and phosphorus atoms, if any, being less than 1/10 a total number of carbon atoms of the organic solvent. The material is excellent in preservability before and after recording and is excellent in heat-developability.

Abstract: Coloring phthalide compounds having general formula [I] ##STR1## R.sup.1 represents hydrogen, an alkyl group, or halogen, m is an integer of 1 to 4, when m is 1, R.sup.2 represents hydrogen, an amino group, an alkylamino group, a dialkylamino group, a cyclic amino group, an alkyl group, or halogen, when m is 2 to 4, R.sup.2 represents halogen, R.sup.3 and R.sup.4 each represent a straight chain or branched alkyl group having 1 to 8 carbon atoms, a cyclic alkyl group, or a benzyl group, and R.sup.5 represents hydrogen, an alkyl group or an alkoxyl group; and a thermosensitive recording material including a thermosensitive recording layer comprising any of the above coloring phthalides and a color developer capable of inducing color formation in the phthalide compound are disclosed.

Abstract: A thermosensitive recording material is disclosed, which comprises (a) a support material; (b) a first thermosensitive coloring layer which comprises a first colorless or light-colored leuco dye having formula (I), ##STR1## and a first color developer having formula (II) capable of inducing color formation in said first leuco dye upon application of heat thereto; ##STR2## (c) a second thermosensitive coloring layer which comprises at least a second leuco dye having formula (III), ##STR3## the first and second thermosensitive coloring layers being formed on the support.

Abstract: A heat-sensitive recording material obtained by coating on a support a composition comprising a microcapsulated colorless or light colored color-forming substance which can develop its color by reaction with an organic base, and an emulsified dispersion prepared by emulsifying an organic base dissolved in an organic solvent insoluble or slightly soluble in water, then drying the coat.

Abstract: A leuco dye having the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each represent a lower alkyl group; R.sup.5 represents an .alpha.-naphthyl group, .beta.-naphthyl group or ##STR2## wherein R.sup.6 represents --NHCOR.sup.9, a halogen or an amino group which is unsubstituted or substituted by one or two C.sub.1 -C.sub.4 alkyl groups which are the same or different; and R.sup.7, R.sup.8 and R.sup.9 each represent hydrogen or a lower alkyl group, provided that when both R.sup.7 and R.sup.8 are hydrogen, R.sup.6 represents --NHCOR.sup.9 or bromine.These dyes absorb in the near-infrared region and yield colored images with a color developer therefor with excellent preservability.

Abstract: Thermally imageable composition comprising (a) at least one leuco dye, (b) a nitrate salt, (c) at least one base having a conjugate acid having pKa equal to or greater than zero. The base serves to prevent spotting or backgrounding of transparency films bearing said thermally imageable composition during the manufacturing process used in preparing the films.

Abstract: A heat-sensitive recording material which comprises a usually colorless or light-colored coloring material together with one or more compounds selected from among bissulfonate compounds, 2-substituted cyclohexyl sulfonate derivatives and biscycloalkyl aryldisulfonate derivatives.

Abstract: A thermosensitive recording sheet having a thermosensitive color developer layer containing a basic leuco dye and an organic color developer, said layer containing a compound of the formula ##STR1## as a sensitizer.

Abstract: A thermoreactive recording material contains a dyestuff precursor and an acid-modified polymer of acrylonitrile or methacrylonitrile and a 4-hydroxybenzoic acid ester as acceptor.

Abstract: The invention relates to novel fluoran compounds of the general formula ##STR1## wherein R.sub.1 and R.sub.2, each independently of the other, are lower alkyl;A is ##STR2## or a pyrrolidinyl, piperidino, morpholino or piperazino radical; and R.sub.3 and R.sub.4, each independently of the other, are C.sub.1 -C.sub.12 alkyl, cycloalkyl, phenyl or phenyl substituted by lower alkyl or lower alkoxy.These compounds are particularly suitable for use as color formers in pressure-sensitive or heat-sensitive recording materials.

Abstract: A positive-acting thermographic material which is black or dark colored in the unexposed condition turns white or light colored when exposed to elevated temperatures. The material comprises a binder, a dark colored complex of ferric iron with a ligand chosen from organothiophosphorus acids, and a white organophosphorus acid or its alkali or alkaline earth metal salt. At elevated temperatures a double decomposition reaction occurs giving the light colored complex of ferric iron with the organophosphorus acid.

Abstract: Compounds of the formula ##STR1## wherein Z.sup.1 denotes hydrogen, alkyl, cycloalkyl or ##STR2## R.sup.1 denotes hydrogen, alkyl, cycloalkyl, aralkyl, aryl, heteroalkyl or heteryl,X.sup.1, X.sup.2 and X.sup.3 denote hydrogen, halogen, alkyl, cycloalkyl, aryl, alkanoylamino, aroylamino or heteryl, and at least one of these radicals denotes NH.sup.1 Y.sup.2, OY.sup.3 or SY.sup.3,Y.sup.1, Y.sup.2 and Y.sup.3 denote hydrogen, alkyl, cycloalkyl, aralkyl, aryl or heteryl andY.sup.1 +Y.sup.2 denote the remaining members of a 5-membered or 6-membered ring which optionally contains further hetero-atoms,are outstanding suitable as color-forming agents for pressure-sensitive, heat-sensitive and electrosensitive recording materials with an acid developer. Deep copies which are fast to light are obtained.

Abstract: Pressure sensitive imaging materials are colorless until pressure addressed, but thereafter provide an intense dark image. The materials comprise white ferric organophosphate, ferric organophosphinate, or ferric organophosphonate and a colorless chelate. The choice of substituents on the chelate nucleus can give images with both good discrimination visually and to near infrared radiation (NIR).

Abstract: Pressure sensitive imaging materials are stable until pressure addressed, but thereafter provide an intense dark image. The materials comprise colorless ferric organophosphate, ferric organophosphinate, or ferric organophosphonate and a colored chelate.

Abstract: An improved thermally-responsive record material having improved image retention is disclosed. The invention is an improved thermally-responsive record member, typically a sheet material, bearing a thermally-responsive color-forming composition comprising a chromogenic material, an acidic developer material, and a metal salt of a compound of the formula ##STR1## wherein M is a metal selected from Zn, Ca, Sn, Ni, Cu, Al, Co, and Mg; wherein m corresponds to the valency of M;wherein n is 1 to 3;wherein R.sup.1 is selected from hydrogen, halogen, alkyl, oxyalkyl, or NO.sub.2, with the proviso that the alkyl group is of 1 to 50 carbons;wherein R.sup.2 is selected from hydrogen, alkyl, or aryl, with the proviso that the alkyl group is of 1-5 carbon; anda suitable binder therefor.

Abstract: A recording material wherein a color forming system comprising (a) a fluorene compound as a dye precursor, (b) a color developer, (c) an isocyanate compound, and (d) an imino compound, gives a developed color image having an absorption at near infrared portion and excellent image storability.

Abstract: There is disclosed a thermosensitive recording material improved in thermal response and image retention which comprises a support and, provided thereon, a thermosensitive recording layer containing a generally colorless or slightly colored dye precursor and a developer which, upon being heated, reacts with said dye precursor to develop color, wherein said thermosensitive recording layer contains as sensitizer a compound selected from a group consisting of p-benzylbiphenyl, diaryl esters of adipic acid, ##STR1## (wherein R represents a substituted or unsubstituted aralkyl group, ##STR2## (wherein R.sub.1 and R.sub.2 each represents an alkyl, aralkyl, or aryl group), and ##STR3## and said developer is bis(3-allyl-4-hydroxyphenyl)sulfone.

Abstract: Disclosed is a heat sensitive sheet which can develop a black image having excellent oil and light resistance, comprising a combination of a record sheet to be printed and a transfer sheet for forming an image on said record sheet, wherein said record sheet is coated with a solution comprising an organic or inorganic nickel compound an an organic and inorganic copper compound and said transfer sheet is coated with dithiooxamide. The present invention also provides a transfer sheet which can form a printed black image having excellent oil and light resistance on any type of record sheets. The transfer sheet is coated with an organic compound having a phenolic hydroxyl group or an amino group directly bonded to aromatic ring and quinone or a quinone derivative substituted by an electron attractive group in such a condition that the organic compound is not reacted with quinone or the quinone derivative.

Abstract: A novel thermally-responsive record material is disclosed which is resistant to image fade from one or more common external challenges including contact with common fats or oils, skin oil, carbonless solvents, plasticizers or high heat and humidity, such as in a 90.degree.F./90% humidity test. The heat-sensitive material of the invention contains a fade resistance imparting ascorbic acid ester of the formula ##STR1## where R.sup.1 is hydrogen or a straight chain or branched chain acyl group of from 9 to 22 carbons inclusive,wherein R.sup.2 is a straight chain or branched chain alkyl group of from 8 to 21 carbons inclusive.

Abstract: A heat-sensitive recording material has a support and a color-developing layer which comprises a particular sulfone as an organic color-developing agent and a particular fluorene-type leuco dyestuff as a colorless basic chromogenic dyestuff. This heat-sensitive recording material is superior in light resistance, weather resistance, oil resistance and optical readability in the near infrared region.

Abstract: A new reversible heat sensitive recording composition for erasable recording is disclosed which is used as a recording or marking material that is capable of erasure at a specific temperature so that coloring or decoloring can be controlled to occur at desired temperature ranges. This range or the hysteresis value of the composition is determined by the .DELTA.T value of the contained ester compound. In addition, the compostion can provide a wide variety of hues and can readily be prepared. The marking or recording drawn in this composition can be maintained at room temperature or less.

Abstract: A recording material containing the combination of at least one electron-donating colorless dye containing a p-substituted aminophenylindolyl azaphthalide and at least one electron-accepting compound containing an organic acid having at least one phenolic hydroxyl group. The material provides colored images having improved stability.

Abstract: A heat-sensitive recording material comprises a support and a color-developing layer having a particular saturated higher fatty acid iron salt, a particular polyvalent phenolic derivative and a colorless leuco dyestuff.The heat-sensitive recording material of the present invention provides both a superior image contrast and a high stability of developed image against oily substances and solvents.

Abstract: A thermosensitive recording material comprising a support material and a thermosensitive coloring layer formed on said support material, said thermosensitive coloring layer comprising a colorless or light-colored leuco dye and a color developer capable of inducing color formation in said leuco dye upon application of heat thereto, the improvement wherein said leuco dye is a compound having general formula (I), ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each represent hydrogen or an alkyl group having a substituent, R.sup.5 and R.sup.6 each represent hydrogen or a phenyl group which may have a substituent, and R.sup.7 represents an alkyl group which may have a substituent or a phenyl group which may have a substituent,and said color developer is a compound having general formula (II), ##STR2## wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 each represent hydrogen or an alkyl group having 1 to 4 carbon atoms.

Abstract: A developer composition comprising first and second developer materials, said first developer material being a finely divided thermoplastic phenolic resin and said second developer material being a finely divided thermoplastic vinylic or acrylic resin containing pendant developer moieties, said first and second developer materials being sufficiently compatible that upon heating they coalesce to form a non-tackey, and scratch resistant film.

Abstract: A heat-sensitive recording material has a substrate and a color-developing layer which comprises a near infrared-absorbing fluorantype leuco dye.This heat-sensitive recording material provides a superior optical readability in near infrared region.

Abstract: A heat-sensitive recording material has a support and a color-developing layer which comprises both as a colorless basic chromogenic dye at least one of a particular fluorane-type leuco dye and a particular divinyl compound and as a stabilizer a particular halogen-substituted zinc benzoate derivative.This heat-sensitive recording material is superior in light resistance, weather resistance, oil resistance and optical readability in the near infrared region.

Abstract: A pressure-sensitive recording medium producing a colored image utilizing the reaction between a substantially colorless electron donating dye precursor and an electron accepting developer is disclosed. This recording sheet is characterized in that the electron accepting developer layer contains an aromatic carboxylic acid metal salt and the electron donating dye precursor layer contains (a) an indolylazaphthalide compound and (b) Crystal Violet lactone.

Abstract: A heat-sensitive recording material is disclosed. The material is comprised of a support having thereon a heat-sensitive color forming layer comprising at least one electron-donating colorless dye and at least one electron-accepting compound, wherein the electron-donating colorless dye is a fluorene derivative having at least one substituted amino group and the electron-accepting compound has an acid group and a solubility in ethanol of 10 or less at 25.degree. C.The material exhibits improved color developability, improved preservability before recording, improved image stability, and improved chemical resistance.

Abstract: The color-developing sheet for pressure-sensitive recording sheets comprises a color-developing agent containing a phenolic polymer in combination with a polyvalent metal salt of carboxylated terpenephenol resin and/or a reaction product of carboxylated terpenephenol resin, aromatic carboxylic acid and polyvalent metal compound.This color-developing sheet provides superior plasticizer resistance and less deterioration of a color-developing ability with the lapse of time.

Abstract: The color-developing sheet for pressure-sensitive recording sheet contains a color-developing agent comprising an inorganic solid acid in combination with a polyvalent metal salt of carboxylated terpenephenol resin and/or a reaction product of carboxylated terpenephenol resin, aromatic carboxylic acid and polyvalent metal compound.This color-developing sheet is superior in both sunlight fading resistance and water resistance.

Abstract: The color-developing sheet for pressure-sensitive recording sheets contains a color-developing agent comprising a polyvalent metal salt of aromatic carboxylic acid in combination with a polyvalent metal salt of carboxylated terpenephenol resin and/or a reaction product of carboxylated terpenephenol resin, aromatic carboxylic acid and polyvalent metal compound.This color-developing sheet provides a higher color-developing rate and a superior color-developing intensity.