Abstract: There is provided a pellicle wherein the pellicle frame is formed with a protrusion which extends either inward or outward from the pellicle frame so that an air passage (vent hole) can extend in it to turn upward or downward to open in the atmosphere or in the pellicle closed space (the space interior to the pellicle frame) so that it is possible to secure a wider opening area for filtration to enable prompt air ventilation whereby the pellicle membrane does not undergo extreme inflation or deflation and thus the pellicle membrane is protected from damages.

Abstract: There are provided a pattern forming method in which, in self-organization lithography using a graphoepitaxy method, high miniaturization of patterns can be achieved with high quality and high efficiency by a pattern forming method including (i) a step of forming a block copolymer layer containing a specific first block copolymer or a specific second block copolymer on a specific substrate, (ii) a step of phase-separating the block copolymer layer, and (iii) a step of selectively removing at least one phase of a plurality of phases of the block copolymer layer, an electronic device manufacturing method using the pattern forming method and the electronic device, and a block copolymer used in the pattern forming method and the production method thereof.

Abstract: A pattern-forming method comprises forming a prepattern that is insoluble or hardly soluble in an organic solvent. A first composition is applied on at least lateral faces of the prepattern to form a resin layer. Adjacent regions to the prepattern of the resin layer are insolubilized or desolubilized in the organic solvent without being accompanied by an increase in a molecular weight by heating the prepattern and the resin layer. Regions other than the adjacent regions insolubilized or desolubilized of the resin layer are removed with the organic solvent. The first composition comprises a first polymer having a solubility in the organic solvent to be decreased by an action of an acid. At least one selected from the following features (i) and (ii) is satisfied: (i) the first polymer comprises a basic group; and (ii) the first composition further comprises a basic compound.

Abstract: An imprinting photo curable resin composition is provided that is excellent in both transferability in imprinting and solvent resistance of the pattern transferred to a structure. According to the present invention, an imprinting photo curable resin composition is provided that at least includes a photopolymerizable (meth)acrylic monomer (A) and a photo initiator (B), wherein the (meth)acrylic monomer (A) is composed at ratios of: (a-1) from 60 to 97 mass % of a trifunctional (meth)acrylate compound; (a-2) from 3 to 40 mass % of a tetrafunctional or higher functional (meth)acrylate compound; and (a-3) from 0 to 37 mass % of a bifunctional or lower functional (meth)acrylate compound (where a sum from (a-1) to (a-3) is 100 mass %).

Abstract: A resist composition contains: a novolak resin (A1) having a protective group capable of being cleaved by action of an acid, an acid generator (B), an anticorrosive agent (G), and a solvent (D) as well as a method for producing a resist pattern includes steps (1) to (4); (1) applying the resist composition according to the above onto a substrate; (2) drying the applied composition to form a composition layer; (3) exposing the composition layer; and (4) developing the exposed composition layer.

Abstract: A resist composition contains: a resin having a structural unit represented by formula (I), an alkali-soluble resin, an acid generator, and a solvent: wherein Ri51 represents a hydrogen atom or a methyl group, Ri52 and Ri53 each independently represent a hydrogen atom or a C1 to C12 hydrocarbon group, Ri54 represents a C5 to C20 alicyclic hydrocarbon group, Ri55 represents a C1 to C6 alkyl group or a C1 to C6 alkoxy group, and “p” represents an integer of 0 to 4.

Abstract: A resist composition contains: a resin having an acid-labile group, an acid generator, a compound having two or more phenolic-hydroxy groups and being other than a resin, and a solvent. The resist composition of the disclosure can provide a resist pattern showing excellent shape and detachability, therefore, the present resist composition can be used for semiconductor microfabrication with resist patterns showing excellent shape.

Abstract: A resist composition contains: a resin having an acid-labile group, a resin having a structural unit represented by formula (I), an acid generator, and a solvent; wherein Ri41 represents a hydrogen atom or a methyl group, Ri42 represents a C1 to C10 hydrocarbon group that may be substituted with a hydroxy group, a C2 to C7 acyl group or a hydrogen atom, Ri43 in each occurrence independently represents a C1 to C6 alkyl group or a C1 to C6 alkoxy group, “p” represents an integer of 0 to 4, Z represents a divalent C3 to C20 hydrocarbon group having a group represented by formula (Ia), and a methylene group contained in the hydrocarbon group may be replaced by an oxygen atom, a sulfur atom or a carbonyl group, *—[(CH2)w—O]r— (Ia): wherein “w” and “r” each independently represents an integer of 1 to 10, and * represent a bonding position.

Abstract: A photosensitive transfer material including a support and a photosensitive resin composition layer, in which the photosensitive resin composition layer includes a polymer component (A) including a polymer having a constituent unit (a1) that includes a group in which an acid group is protected by an acid-decomposable group and a photoacid generator (B), and the photosensitive resin composition layer does not have an ethylenic crosslinking structure is a positive-type material, is excellent in terms of heat-resistant rectangular properties, etchant resistance, and resist peeling properties, and generates only a small amount of dust during processes; a pattern formation method, and an etching method.

Abstract: A photosensitive resin composition, a method of manufacturing a substrate with a template using the composition, and a method of manufacturing a plated article using the substrate with a template. The photosensitive resin composition may be used to form a plated article on a metal surface of a substrate The composition includes an acid generator that, when irradiated with an active ray or radiation, generates an acid, a resin that, under an action of an acid, undergoes an increase in solubility thereof in alkali, and a fluorene compound represented by the formula (1).

Abstract: A photosensitive polysiloxane composition having good adhesion during development, a protective film, and an element having the protective film are provided. The photosensitive polysiloxane composition includes a polysiloxane (A), an o-naphthoquinonediazidesulfonate (B), and a solvent (C). The polysiloxane (A) is obtained via the polycondensation of a monomer component, wherein the monomer component includes a titanium-containing compound (a-1) and a silane monomer (a-2) represented by formula (2). The titanium-containing compound (a-1) is selected from the group consisting of a compound represented by formula (1-1) and a hydrolyzable titanium dimer.

Abstract: A laminated structure for use as a thy film photoresist, which includes a supporting layer, a photosensitive resin layer and a protective layer. The protective layer is a polyester film that has a maximum surface roughness between 1,500 nm and 2,500 nm, and a sheet resistance between 1×108 ?/? and 1×1012 ?/?. The laminated structure is particularly applicable to the manufacture of a photosensitive device and a circuit of a printed circuit board or a lead frame.

Abstract: A hardmask composition may include graphene nanoparticles having a size in a range of about 5 nm to about 100 nm and a solvent.

Abstract: A portable image-forming device includes a housing, an exposure member for exposing an instant film disposed inside of the housing by means of a light radiating from the screen of a portable display device, a shading member linked in movement with the exposure member so as to shade the instant film, a traction member connected to the exposure member so as to move the exposure member to a pre-exposure position, and a developing-agent-spreading member for spreading a developing agent, which is provided on the instant film, over the entire instant film. The traction member and the developing-agent-spreading member are manually operated by a user.

Abstract: A substrate may be disposed on a substrate support in a flood exposure treatment system. A flood exposure dose profile may be selected. The substrate may be exposed to flood irradiation from a source, and the flood irradiation may be terminated when the selected flood exposure dose profile is achieved. Exposing the substrate to flood irradiation may comprise controlling at least one of a substrate rotation rate, a source scanning rate, a substrate scanning rate, a source power setting, a distance from the source to the substrate, a source aperture setting, an angle of incidence of flood irradiation on the substrate, and a source focus position to achieve the selected flood exposure dose profile.

Abstract: A photosensitive resin composition for dry etching including a water-soluble resin, a photopolymerizable monomer, and a photopolymerization initiator, and a method for producing a resist pattern for dry etching. The method includes forming a resin layer with the photosensitive resin composition on a substrate; exposing the resin layer with positional selectivity; and developing the exposed resin layer with water at a temperature less than 50° C., so as to form a resist pattern.

Abstract: Embodiments described herein generally relate to methods for mitigating patterning defects. More specifically, embodiments described herein relate to utilizing field guided post exposure bake processes to mitigate microbridge photoresist defects. An electric field may be applied to a substrate being processed during a post exposure bake process. Photoacid generated as a result of the exposure may be moved along a direction defined by the electric field. The movement of the photoacid may contact microbridge defects and facilitate the removal of the microbridge defects from the surface of a substrate.

Abstract: A surface treatment liquid that can effectively prevent pattern collapse of, in particular, a silicon pattern and a surface treatment process using the surface treatment liquid. The surface treatment liquid contains a water repellent agent and an acid imide. The surface treatment process includes exposing a surface of a substrate to the surface treatment liquid to thereby hydrophobize the substrate surface.

Abstract: A catalytic photoresist composition includes a negative photoresist component and a catalyst component that includes catalytic nanoparticles. The negative photoresist component content is in a range between 30 percent and 95 percent of the composition by weight. The catalyst component content is in a range between 5 percent and 70 percent of the composition by weight.

Abstract: An inspection apparatus (for example a scatterometer) comprises: a substrate support for supporting a substrate and an optical system. An illumination system illuminates a target (T) with radiation. A positioning system (518) moves one or both of the optical system and the substrate support so as to position an individual target (T) relative to the optical system so that the imaging optics can use a portion of the diffracted radiation to form an image of the target structure on an image sensor (23). A liquid lens (722) is controlled (902) by feed-forward control to maintain said image stationary against vibration and/or scanning movement between the optical system and the target structure. In a second aspect, a liquid lens (1324, 1363) to correct chromatic aberration during measurements made at different wavelengths. This may improve focusing of the illumination on the target (T), and/or focusing of an image on the image sensor (23).

Abstract: The invention relates to a method for regulating a light source of a photolithography exposure system which comprises a plurality of LEDs, by means of the following steps: the light output of the individual LEDs in specific wavelength ranges is detected, and the detected light output is compared with a desired light output distribution over the entire spectrum. The LEDs are operated such that the desired spectral light output distribution is achieved in the most precise manner possible. The invention also relates to an exposure assembly for a photolithography device, having a light source which comprises a plurality of LEDs, a control means which controls the electrical power supplied to the individual LEDs, and a sensor which can detect the light output of the LEDs in the respective ranges of the wavelengths.

Abstract: A substrate has three or more overlay gratings formed thereon by a lithographic process. Each overlay grating has a known overlay bias. The values of overlay bias include for example two values in a region centered on zero and two values in a region centered on P/2, where P is the pitch of the gratings. Overlay is calculated from asymmetry measurements for the gratings using knowledge of the different overlay bias values and an assumed non-linear relationship between overlay and target asymmetry, thereby to correct for feature asymmetry. The periodic relationship in the region of zero bias and P/2 has gradients of opposite sign. The calculation allows said gradients to have different magnitudes as well as opposite sign. The calculation also provides information on feature asymmetry and other processing effects. This information is used to improve subsequent performance of the measurement process, and/or the lithographic process.

Abstract: Systems and methods for monitoring the focus of an EUV lithography system are disclosed. Another aspect includes a method having operations of measuring a first shift value for a first patterned set of sub-structures of a focus test structure on a wafer and measuring a second shift value for a second patterned set of sub-structures of the test structure on the wafer. The test structure may be formed on the wafer using asymmetric illumination, with the first patterned set of sub-structures having a first pitch and the second patterned set of sub-structures having a second pitch that is different from the first pitch. The method may further include determining a focus shift compensation for an illumination system based on a difference between the first shift value and the second shift value.

Abstract: An immersion-type exposure apparatus includes a measurement area for measuring a substrate, an exposure area, which differs from the measurement area, for exposing the substrate via a projection optical system, plural stages configured to hold the substrate and to be movable between the exposure area and the measurement area, and a controller configured to control the driving of the plural stages, wherein in a case that one stage of the plural stage is positioned in the exposure area, and immersion liquid that is supplied onto the one stage is retained in exposure area and delivered to another stage, the controller is configured to determine a delivery position of the immersion liquid for the other stage based on at least a first processing position of the other stage.

Abstract: An exposure apparatus is equipped with an encoder system which measures positional information of a wafer stage by irradiating a measurement beam using four heads installed on the wafer stage on a scale plate which covers the movement range of the wafer stage except for the area right under a projection optical system. Placement distances of the heads here are each set to be larger than width of the opening of the scale plates, respectively. This allows the positional information of the wafer stage to be measured, by switching and using the three heads facing the scale plate out of the four heads according to the position of the wafer stage.

Abstract: Provided is an imprinting apparatus that forms patterns sequentially on a plurality of areas of a substrate by using a mold and imprint material. The apparatus includes a moving unit configured to move along a horizontal plane while carrying the substrate, and an adjusting unit configured to adjust an inclination of the mold with respect to the substrate. The adjusting unit adjusts the inclination of the mold with respect to the substrate based on information related to a state of the imprint material provided on the substrate and information related to an order of pattern formation. The information related to the state of the imprint material on the substrate is variable with the movement of the moving unit.

Abstract: Provided is an imprinting apparatus that forms patterns sequentially on a plurality of areas of a substrate by using a mold and imprint material. The apparatus includes a moving unit configured to be movable along a horizontal plane while carrying the substrate on which the imprint material is provided, and an applying unit configured to apply the imprint material onto the substrate based on information related to a state of the imprint material and information related to an order of pattern formation, the information related to the state of the imprint material varying with the movement of the moving unit.

Abstract: The electrophotographic member includes an electro-conductive substrate and an electro-conductive resin layer as the surface layer on the substrate. The electro-conductive resin layer contains a binder and a bowl-shaped resin particle; the surface of electrophotographic member has a concavity derived from the opening of the bowl-shaped resin particle, a protrusion derived from the edge portion of the opening and the electro-conductive resin layer; and when the surface of the member is observed using a scanning electron microscope at an accelerating voltage (1 kV) and a magnification (×2000) while applying a DC voltage (50 to 100 V) between an electrode disposed opposite to the electrophotographic member and the substrate, the brightness of the protrusion, K1, the brightness of the bottom of the concavity, K2, and the brightness of the exposed surface of the electro-conductive resin layer, K3, satisfy K2<K1, K3<K1 and 0.8?K2/K3?1.2.

Abstract: The present invention provides an electrophotographic photosensitive member including a support, and a photosensitive layer on the support. The photosensitive layer has a charge generating layer containing a charge generating material and a charge transporting layer containing a charge transporting material, in this order. The charge transporting layer contains (?) a specific polycarbonate resin or a specific polyester resin, (?) the charge transporting material, (?) a methoxybenzene, and (?) a methoxybenzene, a methoxycyclohexane or a methylhexanol having a substituent. The content W? of the (?) is 0.001% by mass or more and 1% by mass or less based on the total mass of the charge transporting layer.

Abstract: Provided is an electrophotographic photosensitive member including a support, an undercoat layer, and a photosensitive layer in this order, in which: the undercoat layer does not contain a metal oxide, or contains the metal oxide but the content of the metal oxide in the undercoat layer is 10 mass % or less; and the undercoat layer contains a polymerized product of a composition containing at least one kind of anthraquinone derivative selected from the group consisting of a compound represented by the formula (1) and a compound represented by the formula (2).

Abstract: Provided is a fluorine-containing resin particle dispersion including: fluorine-containing resin particles, a resin which is not dissolved in at least one solvent in a group of hydroxyl group-containing solvents including an alcohol-based solvent having 1 to 10 carbon atoms, containing no aromatic ring in the molecule structure, and a water-based medium, and which is adhered on the surface of the fluorine-containing resin particles, and at least one solvent, in which the resin is not dissolved, in the group of hydroxyl group-containing solvents, in which the fluorine-containing resin particles having the resin adhered on the surface thereof are dispersed.

Abstract: A magnetic toner includes toner particles. The toner particles contain a binder resin and a magnetic powder. The binder resin includes a crystalline polyester resin. The magnetic powder has a coating of a melamine resin. Preferably, the crystalline polyester resin has a solubility parameter (SPC) of no less than 9.5, and the solubility parameter (SPC) of the crystalline polyester resin and a solubility parameter (SPM) of the melamine resin satisfy formula (1) shown below. SPC?SPM>1.

Abstract: Provided is a means that can improve performance such as high-speed fixability and fixable temperature range while securing low temperature fixability, in an electrostatic charge image developing toner concurrently using a crystalline resin and an amorphous resin as binder resins constituting toner base particles. An electrostatic charge image developing toner containing toner base particles containing an amorphous resin and a crystalline resin is constituted such that lamellar crystal structures and fibrous crystal structures are dispersed in the cross section of the toner base particles.

Abstract: An electrostatic latent image developing toner includes a plurality of toner particles each containing a binder resin. The toner particles each contain as the binder resin, a crystalline polyester resin and a non-crystalline polyester resin. An FT-IR spectrum of the electrostatic latent image developing toner obtained through FT-IR analysis based on an ATR method has an absorbency peak of at least 0.0100 and no greater than 0.0250 in a wave number range of 701 cm?1±1 cm?1.

Abstract: A method of producing a toner containing a toner particle having a core-shell structure that has a core containing a resin and has a shell phase on a surface of the core, the shell phase being derived from a resin fine particle containing a resin A, and the resin A being a resin containing a segment derived from a crystalline polymer D, the method including steps (i), (ii) and (iii).

Abstract: Provided are a method for producing a negatively-chargeable toner that has a narrow particle diameter distribution even when produced by a polymerization method, and a negatively-chargeable toner that is excellent in balance between low-temperature fixability and heat-resistant shelf stability, has fine thin-line reproducibility, and generates little fog, even in high-speed printing. The negatively-chargeable toner includes colored resin particles which contain at least a binder resin, a colorant, a charge control agent and a softening agent, wherein the charge control agent is a copolymer which is obtained by copolymerizing a vinyl aromatic hydrocarbon, a (meth)acrylate and a sulfonic acid group-containing (meth)acrylamide and in which a copolymerization ratio of the sulfonic acid group-containing (meth)acrylamide is 0.8 to 4.0% by mass, and wherein the softening agent is at least one of a monoester compound and a polyglycerol ester compound.

Abstract: A digital printing apparatus using liquid toner comprising carrier liquid, a dispersing agent and imaging particles, the apparatus comprising: an imaging member adapted to sustain a pattern of electric charge forming a latent image on its surface; a development member arranged to receive a quantity of liquid toner; and to develop said latent image by transferring a portion of said quantity of liquid toner onto said imaging member in accordance with said pattern; a melting unit arranged downstream of the imaging member and configured to melt imaging particles of a transferred part of the portion of liquid toner, said part being transferred from the imaging member, wherein there is provided a dispersing capacity modification unit downstream of the imaging member, said dispersing capacity modification unit being configured for reducing the dispersing capacity of the dispersing agent in the transferred part of the portion of liquid toner.

Abstract: A roller for electrophotography including a mandrel and an elastic layer on the mandrel is provided. The elastic layer contains a hollow particle in a region from the surface of the elastic layer to a depth of 100 ?m. A cross-section of the hollow particle intersected by a first plane and a cross-section of the hollow particle intersected by a second plane each have a ratio of the length of the long axis to the length of the short axis of 1.2 or more and 1.9 or less.

Abstract: A semiconductive roller (1) is formed from a semiconductive rubber composition which contains a rubber component including 15 to 80 mass % of an epichlorohydrin rubber, and has an oxide film (5) formed in its outer peripheral surface (4). The arithmetic average roughness Ra of the outer peripheral surface is 1.0 to 3.5 ?m, and the ratio S/S0 of a measured surface area S per unit area of the outer peripheral surface to a theoretical surface area S0 per unit area of the outer peripheral surface determined assuming that the outer peripheral surface is a smooth surface is 2.0 to 5.0.

Abstract: In an image forming apparatus including a plurality of image forming stations, on the basis of a density of a toner image formed in an upstream image forming station, an operation of a pre-exposure device in a downstream image forming station is controlled.

Abstract: Provided is an optical scanning apparatus, including: a deflection unit; and an imaging optical element (IOE) guiding a light flux deflected by deflection unit onto a scanned surface, in which, an f? coefficient of IOE, a focal length of IOE, and when an intersection between deflection unit and an optical axis of IOE is set as an origin, a coordinate in an optical axis direction (OAD) of an intersection between a principal ray of an outermost off-axis light flux and an incident surface of IOE, a coordinate in OAD of an intersection between principal ray of outermost off-axis light flux and an exit surface of IOE, a coordinate in OAD of an intersection between a principal ray of an on-axis light flux and the incident surface, and a coordinate in OAD of an intersection between principal ray of on-axis light flux and the exit surface are appropriately set.

Abstract: In a case of changing a first light quantity to a second light quantity which is smaller than the first light quantity, a light quantity changing unit changes a light quantity to a third light quantity, which is smaller than the first light quantity and larger than the second light quantity, before changing the light quantity to the second light quantity, and a third light quantity is a light quantity with which the signal is able to be output in a state where a first threshold is set.

Abstract: A method for adjusting a position of a light beam sensor includes preparing a jig at a position coinciding with where the target surface is to be placed, the jig including a sensor mounting section at a reference position where a first beam is to enter, the first beam and a second beam being split from the light beam such that the first beam passes through one or more scan lenses and the second beam enters the light beam sensor, and mounting a reference sensor to the sensor mounting section, the reference sensor being configured to detect the first beam. The method further includes adjusting the position of the light beam sensor so as to synchronize detection timing of the second beam by the light beam sensor with detection timing of the first beam by the reference sensor.

Abstract: An electrophotographic image forming method includes: performing a reversal development process using an electrophotographic photoreceptor including a conductive support, and an undercoat layer, a photosensitive layer, and a surface protective layer, which are at least provided on the conductive support, wherein the surface protective layer includes at least a cured resin and a component capable of influencing frequency dependence of impedance, and the undercoat layer includes at least a metal oxide and has a thickness in the range of 1 to 30 ?m; and performing an electrostatic discharge step including applying an AC voltage at 2 kHz or more, wherein the frequency of the AC voltage is increased depending on use history.

Abstract: An image forming apparatus includes: an image carrier; an image forming unit configured to form, on the image carrier, an electrostatic latent image; a developing unit including a toner carrier configured to develop, on the image carrier, a toner image corresponding to the electrostatic latent image; an application unit configured to apply a lubricant onto the image carrier; a calculation unit configured to calculate an image portion ratio representing a ratio of a toner sticking region to the electrostatic latent image or the toner image; and a control unit configured to cause the lubricant mixed into the developing unit to stick to the toner carrier, and change, depending on the image portion ratio, an amount of the lubricant caused to stick to a non-image-formation region which is a region on the image carrier and in which the electrostatic latent image or the toner image is not formed.

Abstract: A semiconductive roller (1) is provided, which is formed from a rubber composition containing a rubber component including: (1) an epichlorohydrin rubber; (2) at least one solid rubber selected from the group consisting of a solid BR and a solid SBR; and (3) at least one liquid rubber selected from the group consisting of a liquid BR and a liquid SBR.

Abstract: A developing device includes: a casing having a partitioning wall, a toner chamber, and a developing chamber positioned above the toner chamber; a photosensitive drum; a developing roller; a supply roller; first and second conveying members. The developing roller, the supply roller, and the second conveying member are accommodated in the developing chamber. The first conveying member is accommodated in the toner chamber. The partitioning wall has a supply opening and a discharge opening for providing communication between the toner chamber and the developing chamber. The supply and discharge openings are positioned outward of the supply roller in an axial direction of the photosensitive drum. The first conveying member conveys the toner accommodated in the toner chamber into the developing chamber through the supply opening. The second conveying member conveys the toner supplied by the first conveying member from the supply opening to the discharge opening in the axial direction.

Abstract: An image forming apparatus includes an image bearer, an image forming device, a toner concentration detector, a toner supply device, an image density detector, and a controller including a memory device. At a predetermined timing before image formation is started, the controller adjusts a developing potential to adjust an image density of a detection toner image on the image bearer and drives the toner supply device or the developing device to adjust a toner concentration in the developing device. After the image formation is started, the controller drives the toner supply device to adjust the toner concentration, and, in a predetermined sheet interval, adjusts the target concentration based on the image density of the detection toner image formed in a non-image area of the image bearer. When the toner concentration is higher than the target concentration plus a threshold, the controller suspends image formation and readjusts the developing potential.

Abstract: The detection sensitivity of a variation in resonant frequency is increased, and thus a toner concentration is accurately detected. In a sensor device that includes an LC resonant circuit which outputs a pulse signal having a frequency corresponding to the toner concentration, a multiplier portion which multiplies the pulse signal output from the LC resonant circuit and a concentration detection portion which detects the toner concentration based on the pulse signal multiplied by the multiplier portion, the LC resonant circuit includes a detection coil and a capacitor and outputs a pulse signal having a frequency corresponding to the toner concentration. The multiplier portion multiplies the frequency of the pulse signal output from the LC resonant circuit. The concentration detection portion subtracts a predetermined offset pulse number from the pulse signal multiplied by the multiplier portion and detects the toner concentration based on the subtracted pulse number.

Abstract: An image forming apparatus includes a transfer unit that transfers a toner image on an image bearer onto a transfer medium. The image forming apparatus includes a control unit that controls a transfer voltage to be output to the transfer unit in accordance with a certain condition. The control unit applies currents having at least two different values while paper is not being fed. The two current values are lower than a current value during paper feeding. The control unit estimates an output voltage on a basis of a voltage detected through the application of the currents. When the estimated output voltage falls below a certain limiter voltage, the control unit controls to bring the output voltage to a value calculated through the certain condition. When the estimated output voltage exceeds the certain limiter voltage, the control unit controls to bring the output voltage to the limiter voltage.