An image of a reference object is captured using a camera and displayed. A measurement starting point is pointed by an image position pointing device. A corresponding view line is obtained using a position on the image and a position and a direction of the camera, a robot approaches to the reference object such that it does not deviate from a projecting direction to move to a position suitable for measurement. A light is projected on the reference object and measurement of an inclination of a face of the object in the vicinity of a measuring point is started. An image including a bright line image on the reference object is photographed and 3-dimensional positions of points sequentially measured along a working line. A movement path of a robot is created using these positions as teaching points for a working robot.

1. Field of the Invention
The present invention relates to a robot teaching apparatus used in an operation for teaching a motion position to an industrial robot.
2. Description of the Related Art
As a typical technique which is often employed for teaching a motion position of a robot, there is a so-called playback system. When this technique is used, a robot is manually moved to a position where the robot must move actually, and its position is stored in a robot controller.
As another typical technique, there is a so-called off-line teaching. In this technique, using an off-line programming device, an environmental model including a robot and/or an object to be worked is established and a position to which the robot has to move is obtained according to the model by a calculation. The teaching position thus obtained is stored in a robot controller, for example, through a transfer.
When the playback system is employed, since positions required for an operation of the robot (positions to be taught) are taught to the robot one by one, much time and labor are required. It is not rare that the number of teaching positions required for an actual work amounts to a large number (for example, 100).
On the other hand, when the off-line teaching is utilized, it is necessary to input a model of a motion object into an off-line teaching device. In this case, there is a drawback in that, unless a shape of the object is defined as a CAD model or the like in advance, it is difficult to input the shape accurately and much time is required for inputting the shape model.
An object of the present invention is to provide a robot position teaching apparatus which can perform an operation position teaching operation of a robot easily with a high accuracy. Also, another object of the invention is to provide a robot position teaching apparatus which is suitable particularly for a movement path teaching for a robot performing operation while moving along a linear or curved operation route.
For achieving the above object, in the present invention, positions of points on an operating line of a work object are measured by a 3-dimensional position and attitude measuring device (sensor) constituted by a camera and light projecting means. Teaching point data for operating a robot is created from information about 3-dimensional positions of points constituting the working line, which is obtained from this measurement.
The light projecting means projects a pattern light (which is typically a slit light or a spot light) in the vicinity of a point to be measured (hereinafter, referred to as a xe2x80x9cmeasurement pointxe2x80x9d). An object projected with the pattern light is photographed by a camera, and information about a 3-dimentional position of the portion on which the pattern light is projected is captured by image analysis.
Here, as is well-known, in a case where such a pattern light is a slit light, measurement is made by projecting slit lights on a measurement point from two different directions and a 3-dimensional position and an orientation of a face (plane) in the vicinity of the measurement point are calculated from the measurement result.
On the other hand, in a case where such a pattern light is a spot light, measurement is made by projecting spot lights on three or more different points which are not on a straight line and a 3-dimentional position and an orientation of a plane on which these points are positioned are calculated from the measurement result.
In this case, three points positioned near one another are selected and one of these points is set as a target measurement point, or three points (or more points) positioned near a target measurement point are selected and a 3-dimensional position and an orientation of a plane on which the target measurement point is positioned are obtained from the measurement results of these points. For example, the measurement position can be caused to correspond to the geometrical center of gravity position formed by the three points.
Briefly speaking, in the present invention, the 3-dimensional position sensor provided with light projecting means of such a pattern light as a slit light, a spot light or the like and a camera is utilized so that a 3-dimensional position of a target measurement point is measured. Also, an inclination (orientation) of a surface (an area near the measurement point which can be regarded as a flat plane) is calculated together with the measurement of the 3-dimensional position. The attitude of the target measurement point can be represented by this orientation of the surface.
Incidentally, well known is a principle which uses the 3-dimensional position sensor provided with light projecting means of such a pattern light as a slit light, a spot light or the like and a camera to obtain a 3-dimentional position of a target measurement point. That is, by using data obtained through calibration regarding the light projecting means and the camera, a 3-dimensional position of a target point can be calculated within a sensor or the like from the position of a measurement point on an image obtained by the camera and a light projecting state (data representing projecting orientation and position of the pattern light) at this time.
In a case where the light projector or the camera of the 3-dimensional position sensor is mounted on a distal end portion of a hand of a robot, the 3-dimensional position of the target point can once be obtained on a coordinate system (for example, a tool coordinate system) fixed on the distal end portion of the hand of the robot. Even in such a case, by using data about the current position of the robot at this time, the coordinate system can easily be converted to a coordinate system (for example, a world coordinate system, a work coordinate system or the like) fixed to a working space.
Here, when the above target measurement points are sequentially defined and measured along a working line on an object to be measured, teaching points for a working robot for performing work along the working line can be obtained.
In view of the above, a robot teaching apparatus according to the present invention is a robot teaching apparatus of a type that a teaching robot mounted with light projecting means for projecting a slit light or a spot light on an object as a pattern light and a camera is used to perform working along a working line on the object, and comprises: means for obtaining a 3-dimensional position and an orientation of a face of an object on which the pattern light has been projected, from an image of the camera about the face of the object; means for specifying points constituting the working line on the image of the camera; and means for obtaining the specified 3-dimentional positions of the points constituting the working line, on the basis of the 3-dimensional position and the attitude of the face and the positions of the points on the camera image constituting the working line.
By using the robot teaching apparatus according to the present invention, it becomes unnecessary to perform a playback motion on an object robot to be taught. Also, it is not required to constitute a model for an off-line teaching, so that a teaching work for a robot can easily be performed.


Disclosed herein are systems and methods of controlling the pressure in a modulation pressure circuit through transmission fluid through an orificed check valve supplementary or in substitution of a computer-controlled pressure regulation solenoid. Detailed information on various example embodiments of the inventions are provided in the Detailed Description below, and the inventions are defined by the appended claims.

The claimed inventions relate generally to systems that control line pressure in an automatic transmission by a modulation pressure, and more particularly to transmission modification kits that provide line pressure control as a substitute or supplement for computer-controlled line pressure through a modulation pressure circuit and solenoid.
For orientation, the operation of automatic transmissions will now be described. Shown in FIG. 1 are conceptual elements of operation of most automatic transmissions. A pump 1 is configured to receive fluid, typically oil, from a reservoir or pan 4 passing through a filter 3. Pump 1 is driven by rotation of an input shaft coupled to an engine, not shown. In most transmissions a positive displacement pump is used, which is a pump that generates a substantially constant volume per input shaft rotation, or a fluid flow substantially proportional to the rotation of the input shaft. Examples of positive displacement pumps are georotor, gear and vane type pumps. While the input shaft is being driven by rotation of the engine, pump 1 produces a flow of fluid that returns to the reservoir 4 except for a small portion needed for lubrication and to displace valves and servos. Fluid pressure is produced by a main regulator 2 by partially blocking the flow produced by pump 1, which "line" pressure is distributed throughout the transmission through passages 5.
The line pressure is typically provided at a pressure higher than needed by the operating transmission components, and is regulated down to lower operating pressures by auxiliary regulators 6a and 6b. Those lower pressures are provided to the transmission components, in this example valves 7a and 7b and servos 8a and 8b. The arrangement shown in FIG. 1 is merely conceptual; in practice many different configurations of regulators, valves and servos are be used, as is understood by one of ordinary skill in the art.
Fluid pressure may be applied to the several servos in the transmission to provide mechanical operation of the driven components. Those components ordinarily include several clutches and a torque converter, by which the several gears of the transmission are applied to the engine output. An accumulator is normally coupled to the input of a servo, which slows the engagement or disengagement of the servo. Although an accumulator might be implemented by a spring and piston in a bore, conceptually one operates as a balloon. If pressure is increased, an accumulator accepts fluid until an equalibrium is reached. Likewise, as pressure decreases, the accumulator discharges fluid to the new set pressure. The movement of fluid in or out of an accumulator is not instantaneous, but rather is slowed by the fluid passages of the transmission. An accumulator thereby functions to buffer input pressures and graduate the transitions of servo engagement and disengagement.
The gradual operation of servos tends to soften the shifts of the transmission. Sudden gear transitions are undesirable, because passengers feel a lurch or impact and because undue stress is applied to the engine and drive components. Gear shifts that are too soft, however, are also undesirable. During the transition from one gear to another, two clutches may be engaged for a time which increases wear and heat in the transmission. Soft shifts increase this transition time, which decreases the service life of the transmission. A great deal of research and design effort has been made to optimize the shifts in transmissions to balance this tradeoff.
It has been recognized that firm shifts are preferable in some driving circumstances, such as during hard acceleration. Soft shifts, on the other hand, are preferable under other circumstances, for example under light acceleration and coasting. One method of acheiving both hard and soft shifts in the same transmission is to vary the pressure applied to the servos and accumulators. A lower engagement pressure to a servo results in an increased transition time, as more time is required to "fill up" the accumulator. Likewise, a higher disengagement pressure may also be helpful to soften a shift.
One technique used to adjust fluid pressure to servos is through controlling line pressure. A higher line pressure will cause faster servo transition, at least to engagement. As a servo is to be engaged, its accumulator must first accommodate the new pressure. It does so by accepting an amount of fluid which the system must supply through the line pressure. This flow must pass through the various restrictions in the transmission passages, and can do so more rapidly if the head pressure is higher. Thus a higher line pressure will force a greater fluid flow through the transmission passages, which accordingly causes more rapid accumulator adjustment and firmer shifts. This technique also applies to the movement of valves, which also requires some amount of fluid to enter a chamber at the end of the valve bore.
Modulators capable of adjusting fluid pressure have included throttle valves with mechanical linkage and vacuum modulators. These have worked to increase transmission fluid pressure when the throttle is open, intending to cause firmer shifts under that condition. Most recently, modulators have been coupled to an automotive computer/controller that controls the transmission line pressure. Modem automobiles feed a number of sensor inputs into a computer, which then operates to control any number of operational parameters, such as the timing of fuel injectors and spark plug ignition timing. The computer is carefully designed to provide good performance, especially under average driving conditions.
Referring now to FIG. 2A, a line pressure modulation system is shown capable of being controlled by an automotive computer. As in the system of FIG. 1, a pump draws fluid through a filter 3 and supplies fluid flow to a main regulator 5, which provides regulated line pressure 5. Main regulator 2 includes a modulation port by which the line pressure may be controlled, for example, in a modulation circuit at a pressure proportional to the modulation pressure in a given operating range. Restrictions 14 and 15 provide pressure isolation between the modulation port and the input port of the main regulator 2. Restrictions 11 and 12 are conceptual in nature; in practice these restrictions might be provided by passages in the transmission, by regulators, or by other components that supply isolation between the two circuits. A solenoid or modulator 9 is coupled to the modulation pressure 13 providing relief whereby the modulation pressure may be controlled or regulated. A pressure relief valve 10 including a fluid exhaust port is provided to vent a damagingly high modulation pressure 13, which may also limit the maximum line pressure 5 that can be developed in the system. When solenoid 9 in the example is inactive, no fluid flow occurs through the modulation passages under normal conditions. Solenoid 9 may be fully driven to acheive a low modulation pressure 13, or may be partially driven to acheive a moderate modulation pressures through pulse-width modulation techniques, for example by an automotive computer.
The configuration shown in FIG. 2 has two inherent failure conditions. First, if the solenoid should become disconnected from the computer, or if the solenoid became stuck "off," the modulation pressure will rise to its maximum. This failure will result in hard shifts at all times, and may result in damage to transmission components, such as the pump, if line pressure is excessive. In some transmissions cooler and lubrication flow may be reduced or shut-off with excessive modulation pressure, as will be discussed below. Second, if the solenoid should become stuck "on", the modulation pressure will stay low, resulting in soft slippery shifts at all times. This may cause overheating and failure of the transmission, especially for vehicles towing loads up grades.
That configuration has a third failure mode, which is failure of the computer to appropriately command line pressure. The designer of the system may have considered only limited circumstances of use, and designed the computer's program for only the "normal" operational use. For example, it is not uncommon for a single transmission model to be installed to both standard passenger and towing vehicles, despite the large potential difference in total weight. The transmission design may be optimized for a passenger car or a medium duty truck, and may be found to perform acceptably well in the heavy-duty towing vehicle such that an additional transmission model is not necessary to develop or maintain an assembly line for. Under actual use that transmission might be subjected to heavier loads than what the designer intended, because, for example, an operator finds the vehicle engine is sufficiently powered to tow a load up a certain grade. The vehicle's computer may not have a sensory input for the tow weight, and may command soft shifts where firm shifts are called for to avoid transmission overheating. Additionally, most automotive companies do not provide for any automotive computer reprogramming as a solution.
A fourth failure mode may be encountered with the failure of an engine or transmission sensor. It is not unknown for vehicle owners or drivers to continue to operate a vehicle even though the check-engine light is on, indicating that an automotive computer has discovered a problem and recorded a trouble code. Indeed, a vehicle operator may be unmotivated to have the vehicle diagnosed and repaired, due to an expected high cost. Furthermore, some older vehicles were designed only to check for electrical continuity of sensors, and not to detect and flag out-of-range conditions caused by failing sensors. A failed sensor may cause incorrect control of a transmission. For example, a faulty throttle position sensor may cause an automotive computer to erroneously recognize a full-throttle condition as a mid or low-throttle condition. The computer might then command low line pressure for softer shifts, increasing heat and wear. Many other undesirable effects may occur from the failure of other vehicle sensors.
Automotive systems, and especially transmission systems, are operationally complex and require a great deal of knowledge and experience to diagnose and repair problems not frequently encountered. Problems with line pressure are not always perceptible with a vehicle "in the shop," particularly if those problems occur only under special circumstances, for example towing a heavy load up a long and steep grade. Furthermore, it is uncommon for a mechanic or driver to observe transmission line pressure out of the shop because of the difficulty installing a gauge that can be seen from the safety of the inside of a moving vehicle, which might be the only way to directly observe certain transmission performance problems. Trained but inexperienced mechanics may follow the standard flowcharts and/or instructions and observe proper performance under normal conditions, but fail to understand the nature of a particular transmission failure. Furthermore, there has been deficit of understanding of the operational relationship between an automotive computer and a transmission in recent automobiles, which has allowed many transmission problems to continue without a solution for several years. Indeed, there has been a need for a way to provide reliable modulation pressure in a transmission independently of an automotive computer for some time.

Transmission pressure modulation by orificed check valve


A glass composition for use as a laser medium, a method for producing the glass composition, and a laser apparatus including the glass composition are provided. The glass composition includes a host glass; a 3p component having a concentration of about 5 mole percent to about 10 mole percent; and at least one of a 6p component having a concentration of about 1 mole percent to about 5 mole percent and a 5p component having a concentration of about 1 mole percent to about 5 mole percent.

1. Field of the Invention
The present invention is directed to glass composition for use as a laser medium, a method for producing the glass composition, and a laser apparatus including the glass composition.
2. Description of the Related Art
FIG. 1 illustrates a conventional laser apparatus. Referring to FIG. 1, a laser apparatus 100, which is used to emit light for various purposes, typically includes a pumping source 110 for providing energy, a laser medium 120 that receives the energy provided by the pumping source 110, and two reflective elements 130 and 140 to provide feedback of light output from the laser medium. The reflective elements include a fully reflective back mirror 130 and a partially reflective front mirror 140, such that the front mirror 140 transmits a portion of the light through the front mirror as an output of the laser apparatus.
The laser medium 120 may be constructed of various materials, the properties of which affect the operation of the laser apparatus 100, as well as properties of light emitted from the laser apparatus 100, such as bandwidth of the emitted light. Variations in properties of light emitted from the laser apparatus 100, such as a frequency range (i.e., bandwidth), can impact suitability of the use of the emitted light for various specific purposes.
Various fields of science and engineering, in particular, chemistry and telecommunications, require broadband laser sources and optical amplifiers in the form of fibers and waveguides. The Near InfraRed (NIR) spectrum, which ranges from 1100 nm to 1600 nm, is used for wideband operations. Recently, tunable laser action has been achieved using Cr4+ and Cr3+ doped crystals. However, even with these developments, there is still a further need for improved laser medium constructions and compositions in order to produce emitted light even better suited to these and other various purposes.

P-element doped laser medium apparatus and method


The invention relates to a vehicle treatment installation with a drive-in area for a vehicle to be treated, a treatment gantry that can move along a drive-in direction, and at least one camera for creating an image of the drive-in area and vehicle. Such known vehicle treatment installations often fail and/or are maintenance-intensive. The task of providing an installation and also a method for its operation that simplifies, with simple means, the drive-in process into the correct treatment position for the driver of a vehicle to be treated is achieved by a display device that is visible to the driver of the vehicle during the drive-in process, and at least one mark. The subject matter of the invention is also a method for the operation of the vehicle treatment installation.

In the case of known vehicle treatment installations, in particular, self-operated vehicle washing installations, the driver must drive the vehicle to be treated into a specified treatment position. The vehicle is parked there, the driver gets out of the vehicle, and usually starts the treatment program at an input device provided for this purpose on the vehicle treatment installation. Then a treatment gantry with treatment devices arranged thereon, e.g., rotating horizontal and vertical washing brushes or high-pressure cleaning devices, moves once or multiple times over the vehicle starting at the vehicle front toward the vehicle rear end and executes the selected treatment program. In order to achieve optimal treatment, the vehicle must be brought as exactly as possible into the specified treatment position, usually up to a specified stop position in the driving-in direction of the vehicle and centered relative to the open treatment width between gantry posts of the treatment gantry perpendicular to the driving-in direction of the vehicle.
In the case of such vehicle treatment installations, however, the vehicle must be positioned by the driver himself as exactly as possible in the treatment position—which is different than drive-through installations that transport the vehicle in a guided and externally driven way. Many drivers, however, have great difficulties in driving the vehicle easily into the treatment position. Consequently, numerous attempts have already been made to guide the driver into the treatment position by means of different driving aids.
A simple device to help the driver to position the vehicle in the treatment position emerges from JP 60128047 A, which relates to a vehicle washing installation with a washing gantry. In order to bring a vehicle there into the correct treatment position, four rows of knob marks are arranged in the drive-in area of the vehicle washing installation on the base in the area of the wheels of the entering vehicle. So that the driver can recognize the position of his vehicle relative to these knob marks during the drive-in process, mirrors are arranged on the vertical gantry posts of the washing gantry and also on the gantry traverse running perpendicular and connecting these gantry posts. In this simple construction, there is a large disadvantage in that the viewing angle between the driver, mirrors, and the knob marks and vehicle changes continuously during the drive-in process due to the fixed mirrors. In this way, the reflected images of the knob marks and the vehicle that can be seen in the mirrors change continuously, so that the driver quickly becomes confused. If the vehicle enters incorrectly, the driving direction must be changed during the drive-in process, so the reflected images also change. Also, most drivers have problems in correctly reading the assignment of the vehicle movements displayed "mirror-inverted." In this way, the steering correction is often in the wrong direction, so the incorrect position of the vehicle is amplified even more. The drive-in aid with mirrors also has the disadvantage that if there is not uniform lighting of the vehicle washing installation or if light is reflected by the mirrors toward the driver due to light reflections from the vehicle surfaces and vehicle panels, then the driver is temporarily or repeatedly blinded. In the humid environment of a vehicle washing installation, it is also a factor that the mirrors are quickly covered with condensation or dirtied by water drops, so that the mirror images are no longer visible or are only dimly visible.
An alternative drive-in aid according to the class is disclosed in EP 1 090 235 B1. There, the vehicle position of the entering vehicle is determined exactly with a complicated measurement arrangement. With this position data and desired position data stored in the controller of the vehicle washing installation, driving-direction instructions are calculated and then displayed to the driver, showing him in which direction he must steer in order to correctly position his vehicle if it is entering in an incorrect direction. Such complex systems require a high degree of measurement and computational expense, because the driving-direction instructions must be calculated and displayed in real time. In addition, it has been shown that the drivers of entering vehicles often interpret the displayed driving-direction instructions incorrectly or overreact to these instructions and over-steer. Especially for the case of over-steering, the short drive-in area of a vehicle treatment installation results in the vehicle being driven into a position significantly deviating from the desired treatment position, and these position errors are usually made even worse by multiple back-and-forth steering. The errors often can be corrected only by driving out of the treatment installation and driving in again. Often a vehicle is positioned worse due to these drive-in aids than if there were no drive-in aids.
From DE 20 2008 003 961 U1, a vehicle treatment installation is known with a housing that has one or more display devices, e.g., in the form of a flat monitor. Displays of vehicle treatment programs, advertisements, product offers by the installation operator, vehicle treatment tips, current images of the vehicle treatment being performed, or instructions on performing the vehicle treatment could be displayed in the display device. As the drive-in aid, however, this vehicle treatment installation still has the known instruction lights described above in the form of drive-forward and back-up arrows or a STOP light, leading to the problems described above when the vehicle is driven in.

Vehicle treatment installation and method for its operation


The present disclosure discloses an active matrix organic light-emitting diode display device and a manufacturing method thereof. The method includes forming a sacrificial layer on a carrier layer; forming a flexible substrate on the sacrificial layer; forming a first insulating layer on the flexible substrate; forming at least one transition metal chalcogenide based backplane on the first insulating layer; and forming an opening unit after forming a capping layer on the at least one transition metal chalcogenide based backplane; and forming at least one active matrix organic light-emitting diode unit which is electrically connected to the at least one transition metal chalcogenide based backplane in the opening unit.

Transition metal chalcogenides (TMDs) which are classified as two-dimensional materials show excellent physical properties required for devices according to a next generation of electronic or optoelectronics. The transition metal chalcogenides have a multilayered structure and are bonded by the interlayer van der Waals force, so that it is easy to mechanically peel off the transition metal chalcogenides through an adhesive or the like.
The transition metal chalcogenides have been reported to be superior to the existing material because of electrical and mechanical characteristics and are utilized for a large capacity of flexible switching based application based on the material characteristics.
Specifically, since the transition metal chalcogenides provide advantages to switch an organic light-emitting diode on a flexible substrate, such as a high carrier mobility, a high light transmittance, and a low bending stiffness, as compared with an inorganic semiconductor of the related art, a backplane for a flexible organic light-emitting diode (flexible OLED) display is known as one of the most promising applications of the transition metal chalcogenides.
When the transition metal chalcogenides are manufactured by a mechanical peeling method, only pieces having a very small area can be formed so that there is a limit to implement large-area electronic devices. Therefore, studies for high quality and large area synthesis are actively being performed to overcome the above-mentioned disadvantages.
Therefore, a method of synthesizing the transition metal chalcogenides to have a large size corresponding to a wafer size using chemical vapor deposition has been used among synthesizing methods of transition metal chalcogenides.
However, the transition metal chalcogenides grown using the chemical vapor deposition have a difficulty to be applied to a backplane for a flexible system or a large area organic light-emitting diode display due to a low mobility and an inferior semiconductor characteristic caused by a small crystal grain boundary.

Active matrix organic light-emitting diode display device and method of manufacturing the same

INDUSTRY-ACADEMIC COOPERATION FOUNDATION, YONSEI UNIVERSITY


A fine cellulose fiber-containing substance that has excellent dispersibility in water and can be manufactured easily. A method is for manufacturing the fine cellulose fiber-containing substance, and a method is for manufacturing a fine cellulose fiber dispersion. A fine cellulose fiber-containing substance contains fine cellulose fibers into which a phosphite containing a cation of an inorganic substance is introduced. The ratio of the cation of the inorganic substance with respect to 1 g of the fine cellulose fibers is 0.14 mmol or more. In manufacturing the fine cellulose fiber-containing substance, a phosphite is introduced into cellulose fibers, and then the cellulose fibers are defibrated to obtain a dispersion containing fine cellulose fibers, during which an alkali metal ion-containing substance is added to the cellulose fibers, and the dispersion is concentrated. In manufacturing a fine cellulose fiber dispersion, the fine cellulose fiber-containing substance is mixed with water.

In recent years, attention has been paid to nanotechnology aimed at making a substance finer to a nanometer level such that the substance has new physical properties different from conventional properties. Above all, fine cellulose fibers manufactured from pulp are excellent in strength, elasticity, heat stability, and the like, and also contributes to environmental protection. Therefore, expectation for the fine cellulose fibers is large, and an application range thereof is wide. Examples thereof include industrial applications such as a filter material, a filter aid, a base material for an ion exchanger, a filler for a chromatography analyzer, and a filler for blending resins and rubbers, and applications for a blending agent of cosmetics such as a lipstick, powder cosmetics, and emulsified cosmetics. The fine cellulose fibers also have excellent aqueous dispersibility. From this property, for example, use in applications such as food, cosmetics, a viscosity retention agent for a paint or the like, a strengthening agent for a food raw material dough, a moisture retention agent, a food stabilizer, a low-calorie additive, and an emulsion stabilization aid is also expected.
Such fine cellulose fibers expected to be used in various applications are usually obtained by making pulp or the like in a water-dispersed state finer. Therefore, the obtained fine cellulose fibers are in a water-dispersed state (dispersion). However, when the fine cellulose fibers are in a dispersion state, a large amount of transportation energy is required. Therefore, it is necessary to dry the dispersion of the fine cellulose fibers in view of commercialization. However, when the fine cellulose fibers are dried, the fine cellulose fibers are strongly aggregated by hydrogen bonding. For this reason, even when the dried fine cellulose fibers are dispersed again in water, the fine cellulose fibers are not sufficiently dispersed as compared with the state before drying disadvantageously. Therefore, a technique for improving dispersibility (redispersibility) of fine cellulose fibers in a dispersion medium such as water is required.
In this regard, for example, Patent Literature 1 proposes "a method for manufacturing a cellulose nanofiber dispersion, including: a step of mixing cellulose nanofibers with a redispersion accelerator to obtain a gelatinized body; and a step of mixing the gelatinized body, an organic liquid compound, and a dispersing agent to redisperse the cellulose nanofibers". However, this proposal does not dry fine cellulose fibers to a dry state, but merely manufactures a gelatinized body. Moreover, this proposal assumes an organic liquid compound as a dispersion medium.
Patent Literature 2 proposes "a method for drying bacterial cellulose, characterized in that a third component other than bacterial cellulose and water is added to an aqueous suspension containing bacterial cellulose, and then the resulting mixture is dehydrated and dried". However, bacterial cellulose is cellulose produced by microorganisms, and has different physical properties and the like from fine cellulose fibers that can be obtained by defibrating pulp. Therefore, even when this proposal is applied to drying of fine cellulose fibers, a similar effect is not necessarily obtained.
Patent Literature 3 proposes "a method for manufacturing a fine fibrous cellulose redispersion slurry, including: a first step of adding a compound containing at least one kind selected from an alkali soluble metal and a polyvalent metal ion to a fine fibrous cellulose slurry to obtain a fine fibrous cellulose concentrate; and a second step of adding at least one kind selected from tetraalkyl onium hydroxide and alkyl amine to the fine fibrous cellulose concentrate". However, according to this proposal, the step of obtaining a fine cellulose fiber concentrate is complicated. In addition, since an alcohol solution is used for redispersion, a handling property at the time of use of a dispersion after redispersion is poor.

Fine cellulose fiber-containing substance, method for manufacturing the same, and fine cellulose fiber dispersion