JPH1179456A - Paper feeding endless belt and its manufacture and use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a belt much excellent in sheet feedability and durability and its manufacture and use on a paper feeding belt to feed sheets while the sheets are slid by the belt on a sliding body. SOLUTION: In a paper feeding endless belt, an endless belt is formed in a tubular body 1 braided in endless shape with thread braided structure and a coated layer 2 comprising a plurality of linear projected parts provided integrally with point-shaped minute projected parts 4 is provided on the surface of the tubular body at the linear base projected parts 3. For this, for example, weft insertion braid and round braid tubular body formed with wound Tetron (R) thread as a base is coated with urethane rubber. Then an embossing is made by an emboss roll in which linear recessed parts corresponding to the linear projected parts are engraved in the coating layer so as to improve the linear projected parts. This is used as a feeding belt for the feeding part of a copying machine provided with the automatic document feeding part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved endless belt for conveying paper, a method for producing the same, and a use thereof. The belt is effectively used as a member of an automatic feeding section for paper documents in an electrophotographic copying machine.

[0002]

2. Description of the Related Art For example, when copying a paper original by an electrophotographic copying apparatus, generally, the originals are manually placed one by one on a projection glass plate, copied, and then taken out. I have. By the way, when copying a large amount of paper manuscripts,
Since manual operation is very troublesome, an automatic paper document supply / discharge system for automatically supplying and discharging the paper has been developed, and some models are provided inside the lid of the apparatus and commercialized.

In the automatic feeding / discharging system, for example, a paper document deposited on a stocker is sent to a rotating belt via a paper feed guide roll by pressing a start button. The document abutting on the rotating belt slides on the surface of the projection glass plate and stops at a predetermined position (exposure position). Then, when the exposure copying is completed, the belt is driven forward again, and is taken out of the system via a paper discharge guide roll while sliding on the glass plate surface. This is defined as one cycle, and thereafter, the system is automatically repeated.

Here, the functions required for the belt include:
At least the following five items are required. (A) When a paper original is brought into contact with the belt surface and the glass plate is slid, the paper original is
Gliding lightly on the glass surface without slipping (immobile) even with a light touch. (B) The surface of the belt is not stained by accumulation of toner or paper dust. (C) The belt stretched by the guide rolls meanders and does not deviate from a predetermined track. (D) It should be perfectly elastic, but it should be completely elastic. In other words, it should always return to its original size even if it expands with the passage of time. (E) In addition, it does not deteriorate with exposure. The color must be white. It can be mentioned that the production is easy.

[0005] Therefore, various endless belts have been proposed and put into practical use in response to the above demands. For example, the contents are as follows. One of them is 0.5-0.5
An endless polyurethane rubber of about 1 mm in which large and small fine protrusions are randomly formed on the surface. (Hereinafter referred to as Method A) Two of them are endlessly woven (woven structure) as a base cloth, and both sides are coated with a rubber material, and a mesh-like satin finish is applied to the surface layer portion. (See, for example, JP-A-6-1157)
No. 50) (hereinafter referred to as Method B) In three of them, after coating the surface with urethane rubber using an endless woven fabric obtained by partially weaving and weaving conductive fibers, Gear-shaped discontinuous protrusions with a pitch of 0.6 to 0.8 mm, horizontal (with respect to the longitudinal direction)
What was shaped into (Which is considered to be an improvement of JP-A-6-115750). (Hereinafter referred to as Method C)

[0006]

The method A is advantageous in terms of manufacturing since it can be integrally formed by molding. However, in particular, when a mechanism is used in which the belt is stretched and rotated by a ring-shaped roll, dirt considered to be due to toner, paper dust, or the like is formed on the outer (surface) portion of the position in contact with the roll. It is easy to be deposited gradually with use. In addition, the surface protrudes at the contact position, and the flatness is easily lost. These phenomena are probably due to the fact that the entire belt is made of polyurethane rubber itself, which is soft, and that the surface of the portion protrudes due to the pressing force applied to the portion in contact with the roll. It is considered that the state (arrangement, shape, size) of the convex pattern formed on the surface is also related. Furthermore, exposure (with heat generation)
It is considered that this also affects the deterioration of the urethane rubber itself.

On the other hand, in the methods B and C, since a base fabric having a woven structure is used as the substrate, there is no disadvantage due to the softness as in the method A. On the other hand, if it is too hard, meandering due to rotation is particularly likely to occur. Therefore, special measures are required to prevent the meandering. The idea is to coat urethane rubber on both sides of the base fabric to prevent slipping with the tension roller, or to change the material of the yarn to soften the base fabric itself, or to weave. To reduce the thickness,
Further, the rotation mechanism is changed. However, none of these are fundamental solutions, as both make the manufacturing more complicated. In both cases, a slip is gradually generated between the paper document and the belt surface as time passes. This makes it impossible to reliably transport the paper to the home position.
This is probably due to the projections (shape, size, arrangement) formed on the belt surface.
Furthermore, the belt surface is in a state where dirt due to toner, paper dust, or the like is easily generated at an unspecified location. This is also considered to be due to the protruding state.

The present invention has been accomplished as a result of intensive studies to solve the above problems and to find a more excellent endless belt for paper conveyance. Can be achieved by means.

[0009]

That is, the present invention is attained by providing an endless belt for conveying paper, a method for producing the same, and use thereof. The endless belt is a tubular body (1) knitted endlessly by a yarn knitting structure, and the surface of the tubular body has a linear base convex portion (3) and a point-like fine convex portion (4). ) Is provided and provided with a coating layer (2) having a large number of linear projections integrally formed with each other. And dependent on this, Claims 2-7 are provided.

[0010] In the method of manufacturing the endless belt (one desirable embodiment), a liquid elastic resin is coated on the surface of a tubular body knitted endlessly by a yarn knitting structure, as described in claim 8. After coating and drying to form a coating layer, an embossing roll is pressed against the surface of the coating layer under heat and pressure to form a linear base convex portion, a dot-like fine convex portion thereon, and a dot-like fine convex portion thereon. This is a method of shaping a large number of linear projections integrally having fine projections.

Further, the endless belt is particularly for conveying (supplying and discharging) paper, and a specific preferable use is provided in claim 7.
That is, in an electrophotographic copying apparatus provided with an automatic paper document feeder, it is used as a transport belt used in the feeder. The details will be described below.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, in the first aspect, the basic structure of the endless belt for paper transport is a special tubular body (1) and a coating layer (2) having a special linear convex portion on its surface. )). The special tubular body forming the lower layer is knitted in an endless shape by a thread knitting structure, which will be described sequentially. First, the yarn knitting structure is formed by connecting the yarns of synthetic fibers or the like systematically with stitches (units of a combination of loops), and this connection forms a cloth. It is necessary that the cloth form an endless (seamless) tubular shape. Therefore, the conventional B method, C method
It is essentially different from a weaving structure like a law, that is, a weft yarn and a warp yarn connected in a crossing manner and woven in an endless shape.

The specific differences regarding the above-mentioned essential differences are as follows. First, since the knitting structure has stitches, the eyes are slightly open. Thereby, appropriate flexibility can be obtained. In addition, there must be elastic elasticity.
And it can be knitted into a tube in a substantially seamless state. On the other hand, the woven structure has characteristics opposite to those of the knitted structure. That is, the eyes are not substantially opened, that is, the eyes are dense and the whole is hard. It is rigid without substantial expansion and contraction, and the joint at both ends of the circular weave is not completely flat.

[0014] However, the knitted structure is in a soft state with elasticity and in an open stitch.
This means that the resin forming the coating layer penetrates into the eyes, so that the coating layer may be formed on only one side, and the adhesion between the layer and the knitting structure, and also the overall elasticity and strength, may be on the front and back surfaces. There is no difference and it is uniform. By coating the coating layer into the eyes of the knitting structure, it is not necessary to coat both sides as in the method B.
It is not necessary to provide antistatic properties by using conductive fibers for some yarns of the woven structure as seen in the law, that is, if the coating layer contains an antistatic agent, from the front to the back This is because they conduct and provide antistatic properties.

The type of knitting structure is 44 (JI
S Handbook 54 Fiber, 1992P 121-124). In the present invention, since all of them are targeted, it is not specified, but among them, warp insertion knitting or weft insertion knitting is preferable. Of course, warp and weft insertion knitting by both of them may be used. This is because the insertion and knitting of the weft and warp yarns can control more excellent elasticity and strength, and furthermore, control the required degree of opening of the eyes. Here, the weft insertion knitting is such that the yarn is linearly (no stitch is formed) inserted into the stitch from the lateral direction over the entire width of the endless tubular body, and FIG. Is as shown in FIG. FIG. 2 shows a straight line in the weft knitting (loop) 5 (no stitch is formed).
And weft thread 6 inserted. Figure 3 is a vertical knitting (loop)
FIG. 7 is a plan view when a straight weft thread 8 is inserted inside 7. On the other hand, in the warp insertion knitting, the yarn is linearly inserted into the stitch from the longitudinal direction over the entire width of the endless tubular body, and a part thereof is shown in a plan view in FIG. In other words, it is a knitting structure in which the warp yarn 11 is inserted into the warp / weft knitting composed of the weft knitting 10 and the warp knitting 9.

The yarn to be knitted is made of a natural fiber, a semi-synthetic fiber, a synthetic fiber (synthetic fiber), or a yarn made of any of these fibers. . Further, even in the case of this synthetic fiber, it is more preferable that the fiber is a polyester fiber, especially a tetron, which is also a crimped yarn that has been crimped, rather than being linear. This is because it becomes more elastic and it is more convenient to control the open state. In addition, the thickness (fiber thickness and number of bundles) as a thread shape affects the hardness, thickness, strength, etc. of the base fabric. It is better to decide, but it is better to decide in the smaller direction than the larger.

Next, the coating layer (2) will be described. The coating layer is basically formed of a synthetic resin, but it is desired that the resin is soft for use as a belt. Among these soft resins, those having elasticity are preferable. As the resin having this elasticity, for example, a resin exhibiting an all-effect elastic behavior seen in a thermoplastic elastomer (styrene-based, olefin-based, PVC-based, urethane-based, ester-based, amide-based), and furthermore, a resin close to ideal elasticity, Resins generally called rubbers include, for example, butadiene rubber, urethane rubber, silicone rubber, and fluorine rubber. Among these elastic resins, urethane-based rubbers which are easy to obtain various rubber hardness, excellent in strength (tear, etc.), and further excellent in moldability (molding into a certain shape, coating property) and adhesion to a knitted base fabric, etc. Particularly preferred.

The coating layer is not a simple plane layer, but firstly, a large number of linear projections serving as a base, that is, a plurality of linear projections are provided at predetermined intervals. This is a coating layer having a specially shaped linear protrusion in which a large number of point-like fine protrusions are integrally provided at a predetermined pitch. Here, "integrally" means that the formation of the linear projections is the same as the material for forming the coating layer or that the material is a blend containing the material as a main component.

Here, since the coating layer itself has a special linear convex portion, contamination due to toner, paper dust, etc. among the problems of the conventional methods A to C is not deposited. Therefore, the generation of dirt is extremely small even when used for a long time. This is presumably because even if there is dirt, it can be carried away with the paper each time it is used. It is considered that this effect is due in particular to the action of the linear base protrusions at predetermined intervals. And, by the presence of the point-like fine projections on the base projections, the non-slip property to the paper is extremely improved, and the slippage does not occur even with a very light touch. ,
The non-slip property can exhibit a remarkable effect that it is constant throughout.

The shape, size, and arrangement relationship between the linear base protrusions and the dot-like fine protrusions are determined by detailed examination so as to exert a greater effect in relation to the use conditions. However, it is good to aim at this as a preferable range. First, the shape of the point-like fine convex portion is a circular or polygonal shape (preferably a quadrangle), and the size, particularly the height, is about 0.1 to 0.5 times the height of the base convex portion. Is good. If it is higher than 0.5 times, the durability (for example, falling down) against repeated use is reduced. On the other hand, if the ratio is lower than 0.1, the dynamic friction between the paper and the paper becomes small, so that the paper slips easily and it becomes difficult to carry the paper smoothly. The line width is desirably the same as or slightly smaller than the base convex portion.

The shape (cross section) of the linear base convex portion is preferably a right angle or a conical shape, and its line width is about 50 to 200.
μm, preferably about 70 to 150 μm, and a height of about 20 to
It is 100 μm, preferably 30 to 80 μm. Also,
The arrangement is such that the pitch width is about 0.5 to 2 mm, preferably 0.7.
It is better to provide a large number of 1.5 mm. The base protrusions may be provided so as to cross each other, or may be provided in one direction only. Here, in the case of the above-mentioned crossing arrangement, it is preferable to form them obliquely (to form a rhombus) with each other. In the case of only one direction, it is preferable that the angle is a diagonal direction of the right fork or the left descent rather than the horizontal or vertical direction. Among them, it is preferable that the right and left forks in one direction or the left and down slopes are arranged in multiple rows.

Incidentally, in order to clarify all the configurations according to the above-mentioned (1) to (5), the description will be made with reference to the drawings as shown in FIG. FIG. 1 is a diagram showing a part of the endless belt of the present invention and showing a slanted cross section thereof. First, there is a tubular body 1 knitted by a knitting structure,
There is a coating layer 2 of an elastic resin on the surface. The coating layer 2 has, on its surface, a linear base convex portion 3 serving as a base of the linear convex portion, and further has a dotted fine convex portion 4 thereon.
Has become. The linear base projections 3 are arranged in multiple rows at a predetermined interval with a downward slope. Further, the point-like fine convex portions 4 are also provided on the entire surface at a predetermined pitch, and this pitch also affects the non-slip property on paper. Therefore, the desired pitch may be determined by an experimental test, but in general, a preferable result can be obtained by setting the pitch to about 0.5 to 2 mm. The cross section of the tubular body 1 is indicated by 1a,
And the cross section of the coating layer 2 is shown by 2a. It can also be seen that a portion of the elastic resin 2a has penetrated into the eyes of the tubular body 1, has reached the back surface, and is blocking the eyes.

The coating layer 2 may contain various necessary additives. For example, there may be mentioned light stabilizers, antioxidants, surface roughening agents, antistatic agents, flame retardants, coloring agents and the like. Above all, it is preferable to use a combination of titanium oxide and an antistatic agent, which has both roughening and coloring, for example, because it further improves non-slip properties with paper and suppresses adhesion of toner, paper powder and the like. In addition, the belt is colored white, so
Visual recognition of scratches and the like is also facilitated. The content of these additives is
For example, in the case of titanium oxide, the amount is about 10 to 50% by weight, and the amount of the antistatic agent is about 10 to 25% by weight, based on the solid matter (coating layer). The antistatic agent has a low molecular weight to a high molecular weight in terms of molecular weight, and electrically has three kinds of anions, cations and non-ions. An appropriate one may be selected from among them. However, among them, a high molecular weight cationic antistatic agent is preferably used. Examples of this include acrylic polymers in which a quaternary ammonium salt is bonded to an amide group (eg, Daiichi Kogyo Seiyaku Co., Ltd., Leorex AS170).
There is. This is particularly effective when the coating layer forming raw material is a urethane rubber.

Next, a method of manufacturing the endless belt according to the present invention will be described. In addition, the said manufacturing method is one preferable form, and is not limited to this. First, what kind of yarn, what kind of knitting structure, how much stitch (opening degree), what size of the tubular body (thickness, width, circumference), how to insert After setting the conditions such as what to do, prepare a circular knitting machine that meets the conditions, and the required endless fabric (tubular body)
Knit.

Then, a liquid elastic resin (elastic resin dissolved in an organic solvent) is applied on the surface of the obtained endless cloth (tubular body) once or several times so that a predetermined final layer thickness is obtained. And apply and dry. The predetermined layer thickness is appropriately determined in consideration of the overall balance (hardness, linear projection).
Generally, it may be about 0.3 to 1 mm. Here, when there are wrinkles or the like on the surface of the fabric and the flatness is adversely affected, it is desirable to perform a treatment for removing it. The treatment method is, for example, stretching the fabric on two rolls,
A pressing roll is provided facing the roller, and pressing is performed while rotating under heat and pressure. As a means for coating, various commonly used methods can be used, and among them, a roll coating method is preferable. After a predetermined nip width is provided, two stretched rolls are rotated and continuously applied, and then dried (at least a temperature at which the organic solvent is evaporated). When a predetermined coating layer thickness cannot be obtained by one application and drying, the same operation is repeated. This application
When drying is completed, the process for forming the next linear convex part is started.
Before entering this step, the following preliminary processing may be performed.
This is the case where the surface of the coating layer is not smooth or the layer thickness is uneven. For example, in the case of the above-mentioned cloth, it is preferable to carry out the treatment according to the example of the treatment by rolling under heating and pressure. The pressure is determined by the temperature and the state of the layer surface, and the temperature is preferably determined with the softening point of the elastic resin as a target.

Finally, a desired linear convex portion (consisting of a linear base convex portion and a point-like fine convex portion) is formed on the surface of the coating layer. There is no particular limitation on the shaping means. .
For example, there are a screen printing method, a masking method using a mask plate, and an embossing method using an embossing roll. Among them, the embossing method is preferable. This is because the desired linear projection can be reliably and quickly formed. Therefore, this embossing method will be described more specifically.

The shaping by embossing is performed by embossing a roll (gravure roll) in which a concave portion corresponding to a desired linear convex portion (consisting of a linear base convex portion and a dot-like fine convex portion as described above) is provided on a metal roll. In this case, the embossing (generally, rolling under heat and pressure) is performed, but more specifically, by the following means.

For example, on one of the metal rolls, first, a linear concave portion corresponding to the linear convex portion is formed by engraving (by manual or laser) or etching (photolithography and corrosion by inorganic acid). I do. Next, a point-like fine concave portion corresponding to the point-like fine convex portion is engraved in the base concave portion. Here, each of the concave portions has a desired shape and size (line width, height) of a linear convex portion.
On the other hand, it is preferable to make it slightly larger. This is because the embossing method is generally reproduced in a reduced scale. It is desirable to confirm by a preliminary test how large the device should be manufactured. Then, the obtained embossing roll is attached to an embossing device, and is continuously embossed under heating and pressing. Thereby, a desired linear convex portion can be formed at once.

The embossing device basically has a plurality of metal rolls (depending on the size of the tubular body) for stretching and rotating the tubular body provided with the coating layer, and faces the metal roll. Consists of embossing rolls
The embossing roll is provided with a pressure adjusting means and a heating means.

The heating and pressing at the time of embossing are carried out by operating an embossing roll. The condition may be determined by confirming a preliminary test. According to the conditions of preliminary treatment (surface smoothing)
In particular, it is preferable to set the pressure slightly higher.

As another specific method, for example, when a desired linear convex portion is formed obliquely in one direction, first, only a concave portion corresponding to the linear base convex portion is formed obliquely in one direction. Using two embossing rolls (called A-roll) made in a pattern and another embossing roll (called B-roll) made in a reverse oblique pattern so as to cross this pattern, Embossing is performed twice by being attached to the embossing device. What is important here is that at least the pressing by the A roll and the B roll is not the same, and it is necessary to reduce one of them. By reducing the pressing force of at least one of the rolls, the desired linear base protrusion can be left, and the desired point-like minute protrusion can be formed at the intersection. Therefore, since the pressure difference mainly depends on the size of the desired linear base convex portion and the point-like fine convex portion, what kind of pressure difference should be set is determined by performing a sufficient preliminary test. Is good. It should be noted that, in addition to the difference in pressure, the speed and temperature of embossing may slightly depend on the case. In the case of being influenced by these, first, the first embossing is performed by the A or B roll, and then the setting is performed at a different speed and temperature from the first by the B or A roll. The second embossing is performed.

Further, the size (depth and line width) of the recesses formed in the A or B roll may be the same, or one of the recesses may be a shallow recess. It is preferable that the depth of the roll to be made shallower is slightly deeper than the depth of the desired point-like fine projections, which is a considerable reference.

Further, the second linear embossing (embossing for forming point-like fine convex portions) slightly deforms (has a large line width and a low height) the desired linear base convex portions. May be shaped. The presence or absence of this slight deformation should be confirmed by a preliminary test, and this should be taken into account when producing the embossing roll.

The paper transport endless belt of the present invention is effectively used as one device of a transport device for transporting paper while sliding it on a sliding body. The present invention is used as a transport belt of an automatic paper document feeder provided to face a projection glass plate. The incorporation of the belt into the automatic feeding section has no difference between all models generally used and can be attached with the same mechanism.

[0035]

The present invention will be described in more detail with reference to the following examples together with comparative examples. In the examples, the elongation at break (%), the volume resistance (Ω · cm), the coefficient of kinetic friction between paper and a glass plate,
The light resistance (weather) resistance and the degree of surface pencil stain were measured under the following conditions. ○ Elongation at break (%): According to JIS K6732
A value measured by a tensile tester AGS-100A manufactured by Shimadzu Corporation. This value is related to the elasticity, but if it is too large, it is not preferable because the stretched belt elongates with time during roll rotation. ○ Volume resistance (Ω · cm) ・ ・ ・ 420-450μ
The value measured with a resistance meter Hiresta IP manufactured by Mitsubishi Yuka Co., Ltd. when a voltage of DC 100 V and a voltage of 30 seconds were applied to the m belt test piece. The smaller, the better the antistatic properties. O Dynamic friction coefficient on paper: HEIDON-14DR manufactured by Shinto Chemical Co., Ltd. in accordance with ASTM-D-1894 in a state of sliding on copy paper (A4 size) with the linear convex surface of the belt test piece in contact therewith. Value measured in. O Dynamic friction coefficient to glass plate: HEIDON-14D when a glass plate is used instead of the copy paper
Measured value by R. A belt that is larger for paper and has a smaller coefficient of kinetic friction for a glass plate can transport the paper more reliably and more quickly. Also, there is no jam due to rotation, and the belt can be always rotated with a constant orbit. ○ Light resistance (weather): 60 ° C. with Sunshine Weather Meter FAX-25AX-HC manufactured by Suga Test Instruments Co., Ltd.
The change in color (white) at the time of continuous irradiation for 100 hours was measured. A blank (non-irradiated belt test piece) is classified into class 4 and evaluated in four stages of class 4 to class 1. O Surface pencil stain: The endless belt obtained was mounted on a commercially available copying machine equipped with a paper original automatic feeder, and the occurrence of stain was confirmed by the following practical test and measured. That is, a copy of A4 size copy paper drawn in a lattice pattern (10 mm pitch) with a pencil was used as a copy original, and 3000 sheets of this were continuously supplied and copied. This 3
When copying of 000 sheets was completed, the belt surface was visually checked for the presence of pencil stains. When there was no dirt, it was judged that there was no dirt. When there was dirt, it was evaluated that there was dirt regardless of the degree.

Example 1 First, knitted tetron yarn was knitted endlessly using a circular knitting machine with a weft insertion knitting structure shown in FIG. The obtained endless woven fabric (tubular body) has a thickness of about 300 mm, a width of 400 mm,
The circumference (outside) was 1025 mm. Here, some wrinkles were observed on the surface, and the following treatment was performed to make the whole more planar. In other words, two metal rolls with a motor drive are fixed, and the knitted fabric is stretched firmly on the two rolls. Then, a pressure roll is also provided to face one of the rolls. The whole of these is accommodated in a heating chamber, and the opposing pressure roll incorporates a variable pressing mechanism against the knitted fabric. Heating room is 120 ° C
The pressure roll was slowly rotated back and forth five times by applying a linear pressure of about 7 kg / cm ^{2 to} the pressure roll. The surface of the knit obtained by this treatment had no wrinkles, and the whole had a firmer feeling. This is hereinafter referred to as an endless knitted fabric.

On the other hand, two types of urethane rubber solutions having the following compositions were prepared, and used as solution A and solution B, respectively. (Solution A): 300 g of ester-based polyurethane having a rubber hardness (Shore A) of 50 to 55 °, 100 g of a crosslinking agent (aliphatic diamine), 250 g of Leorex AS170 (antistatic agent), and N, N′- Ester polyurethane solution comprising 1100 g of dimethylformamide (organic solvent) (viscosity 5000 cps) (Solution B): 225 g of ester polyurethane having a rubber hardness of 45 to 50 °, and Leorex AS170
Ester polyurethane solution (viscosity: 1000 cp) composed of 110 g of titanium oxide powder, 200 g of titanium oxide powder and 1100 g of N, N-dimethylformamide Next, the obtained solution A and solution B are coated on an endless base fabric by the following method to form urethane. A rubber coating layer was provided.

First, the endless knitted fabric was stretched on a separately provided coating device, and the solution A was roll-coated (undercoated) while rotating at a speed of 500 mm / min. At this time, the clearance between the belt surface and the roll coater was 200 μm. After coating the entire circumference, rotation was continued at room temperature for 5 minutes, then, solution B was coated (overcoated) under the same conditions, and finally, hot air at 155 ° C. was applied to the coating surface and heated for 20 minutes. By this heating, most of the dimethylformamide was removed by evaporation together with the crosslinking reaction of the ester-based polyurethane. Further, the obtained endless knitted fabric having the urethane rubber coating layer is removed from the apparatus, and this is stretched on the rotating roll with the pressing roll, and the pressing is performed at a pressure of 3 kg / kg.
The coating layer was pressed while rotating at a temperature of 120 ° C. at a temperature of ² cm ² to smooth the coating layer, and this step was completed. What has been subjected to this surface smoothing treatment is hereinafter referred to as a rubber belt / knitted substrate.

Next, the rubber belt / knitted substrate was embossed with an embossing device under the following conditions to produce an endless belt for paper conveyance provided with a coating layer having a target linear convex portion. The embossing device used here is composed of two metal rolls for stretching and rotating the knitted base, and two emboss rolls provided to face the two metal rolls. The embossing roll has an infrared heater capable of controlling the temperature inside the embossing roll, and a pressing load mechanism capable of finely adjusting the temperature.

One of the two embossing rolls is 4
With a concave line descending to the right at an oblique angle of 0 °, another is 40
These were made by engraving with concave lines descending to the left at an oblique angle of ゜, each having a width of 200 μm, a depth of 120 μm, and a distance between concave lines of 1 mm.

The embossing by the embossing device was performed under the following conditions. First, the surface temperature of one embossing roll was adjusted to 130 ° C., and the temperature of the other roll was adjusted to 110 ° C., and from the higher temperature, pressing was performed at 6 kg / cm ² and embossing speed was 750 mm /. Embossed in minutes. As a result, the linear base convex portion was shaped rightward or leftward. Then, using the roll having the lower temperature, embossing was performed at a pressure of 2.5 kg / cm ² and an embossing speed of 1000 mm / min. As a result, a point-like fine convex portion was formed at a position intersecting with the linear base convex portion, and a desired linear convex portion could be obtained.

The linear projections formed on the surface of the coating layer of the obtained rubber belt knitted substrate had a width of 210 μm,
The linear base protrusion having a height of 70 μm (corresponding to 3 in FIG. 1) is 40
At an angle of ゜, in an oblique direction at 1 mm intervals, and on the linear base convex portions, approximately 200 μm square point-shaped fine convex portions (corresponding to 4 in FIG. 1) having a height of approximately 30 μm are formed at a pitch of approximately 1 mm. Was formed. Hereinafter, this is referred to as an endless belt A.

The performance of the endless belt A was evaluated. The results were as follows. ○ Elongation at break (%) ・ ・ ・ 20 ○ Volume resistance ・ ・ ・ 2.9 × 10 ⁹ Ω ・ cm ○ Dynamic friction coefficient for paper ・ ・ ・ 1.15 ○ Dynamic friction coefficient for glass plate ・ ・ ・ 0.23 ○ Light resistance: 4th grade (no discoloration) ○ Surface pencil stain degree: None In addition, the presence or absence of jam due to rotation was checked together with the surface pencil stain degree, but there was no such occurrence. It was also confirmed that the gas was smoothly supplied and discharged with a constant orbit.
Each of the above-mentioned performances completely clears the performance required particularly as a belt member of an automatic feeding section (feeding and discharging) of a copy original in a copying machine.

(Comparative Example 1) First, using the same Tetron-wound yarn as in Example 1, weaving was performed on a woven structure (a right-angled cross between warp yarns and weft yarns) using a bag loom, and was about 200 μm thick and 400 mm wide. And an endless woven fabric having a perimeter (outside) of 1020 mm was obtained. The woven fabric was pressurized under heating under the same conditions as in Example 1 to smooth the surface.
The obtained product was denser and harder than the endless knitted fabric in Example 1, and had no openings as far as the naked eye could see it. Hereinafter, this is called an endless woven fabric.

Next, the upper surface of the endless woven fabric was coated with the liquid A first under the same conditions using the coating apparatus used in Example 1, and then the liquid B was further coated thereon by roll coating, followed by heating and drying. Thus, an endless woven fabric laminated with the same urethane rubber coating layer was obtained. Further, this was applied under pressure and heat (3 kg / cm) under the same conditions as in Example 1.
² , 120 ° C.) while rotating to perform a surface smoothing treatment. Hereinafter, this is referred to as a rubber belt / woven substrate.

Next, the coating layer of the rubber belt / woven substrate was embossed with the same embossing device as in Example 1. However, embossing was performed only once with an embossing roll performed at the higher temperature (130 ° C.). Therefore, the only convex portions formed on the coating layer surface are linear base convex portions (corresponding to 3 in FIG. 1), and no point-like fine convex portions (corresponding to 4 in FIG. 1) are provided. The obtained linear base projection has a width of 220 μm, a height of 83 μm, and a width of 40 μm.
It was regularly shaped obliquely at 1 mm intervals at an angle of １. Hereinafter, this is referred to as an endless belt B.

The performance of the endless belt B was evaluated in the same manner as the endless belt A, and the following results were obtained. ○ Elongation at break (%) ・ ・ ・ 23 ○ Volume resistance ・ ・ ・ 1 × 10 ¹⁴ Ω ・ cm ○ Dynamic friction coefficient for paper ・ ・ ・ 0.86 ○ Dynamic friction coefficient for glass plate ・ ・ ・ 0.3 ○ Lightfastness Properties: Grade 4 (no discoloration) ○ Surface pencil stain degree: Yes Also, there was occurrence of jam due to rotation. This is probably due to a slight slip between the roll.

The reason why the volume resistance value is abnormally large is that the urethane rubber forming the coating layer does not substantially penetrate into the weave, and therefore the woven fabric is an electric insulating layer. Conceivable. This is considered to be related to the occurrence of jam. That is, in Example 1, the urethane rubber reached the back surface through the weave, and was in a state of conduction between the front and back surfaces, whereas in this example, the urethane rubber did not penetrate to the back surface. This is considered to be due to the occurrence of jam due to the occurrence of slip between the rolls. Further, the dynamic friction coefficient with respect to the paper and the glass plate is greatly different from that of Example 1, and this difference is considered to be a difference in the effect particularly due to the presence or absence of the point-like fine convex portions. In particular, this result leads to the occurrence of jams more and more over time, and the inability to smoothly and automatically feed and discharge paper documents. Also, the presence of surface pencil stains is considered to be due to the fact that the present example does not have point-like fine convex portions.

[0049]

As described above, the present invention has the following advantages.

First, even when used for a long time, the belt surface does not protrude at all, maintains the flatness at all times, and does not deteriorate due to the light source used in the copying machine.

Even when used for a long time, there is no slip between rolls and no jam occurs, and paper can be fed and discharged accurately and quickly.

Even when copying for a long time, the belt surface is not stained at all by the copy original written with a pencil or the like.

In addition, it is not necessary to provide a coating layer on both sides, and the same effect (non-slip property to a roll and antistatic property) can be obtained by laminating a coating layer on only one side. In addition, since the coating layer is formed in a state in which the coating layer is completely adhered to the knitted fabric, the coating layer never peels off from the knitted fabric. The endless belt according to the present invention is effectively used for an apparatus which takes a means for transporting any paper while sliding it. Among them, a member of an electrophotographic copying apparatus with an automatic copy original feeder is particularly used. As more effective.

[Brief description of the drawings]

FIG. 1 is a partially oblique sectional view showing an example of an endless belt for conveying paper according to the present invention.

FIG. 2 shows an example of a knitting structure in the present invention by a weft insertion knitting. (Plan view)

FIG. 3 shows an example of a knitting structure according to the present invention by a weft insertion knitting. (Plan view)

FIG. 4 shows an example of a knitting structure according to the present invention by warp insertion knitting. (Plan view)

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tubular body (base cloth) by knitting structure 2 Coating layer 3 Linear base convex part 4 Point fine convex part 5 Weft knitting 6 Weft 7 Warp knitting 8 Weft 9 Warp knitting 10 Weft knitting 11 Warp knitting

Claims (9)

[Claims] 1. An endless belt for conveying paper, wherein the endless belt is a tubular body (1) knitted endlessly by a thread knitting structure, and a linear base convex portion ( 3) An endless belt for conveying paper, wherein a coating layer (2) having a large number of linear projections integrally having point-like fine projections (4) is provided thereon. 2. The endless belt for conveying paper according to claim 1, wherein the yarn knitting structure is a warp insertion knitting or a weft insertion knitting made of chemical fibers. 3. The paper conveying endless belt according to claim 2, wherein the chemical fiber is a crimped tetron yarn. 4. The point-like minute convex portion (4) is circular or polygonal in shape, and its height is 0.1 of the height of the linear base convex portion (3).
2. The endless belt for paper conveyance according to claim 1, wherein the ratio is from 0.5 to 0.5 times. 3. 5. The linear base projection (3) has a line width of 50 to 200 μm.
m, height of 20 to 100 μm, and 0.5 to 2
The paperless endless belt according to claim 1, wherein a plurality of belts are formed in one direction at an interval of mm. 6. The paperless endless belt according to claim 1, wherein the coating layer (2) is made of an elastic resin containing titanium oxide and an antistatic agent. 7. The paperless endless belt according to claim 6, wherein the elastic resin is a urethane rubber. 8. A coating layer is formed by applying and drying a liquid elastic resin on the surface of a tubular body knitted endlessly by a yarn knitting structure, and then an embossing roll is pressed against the coating layer surface under heating. The method according to any one of claims 1 to 7, wherein a large number of linear protrusions integrally having a linear base protrusion and a dot-like fine protrusion thereon are formed. Of manufacturing an endless belt for paper transport. 9. The paper transport according to claim 1, wherein said paper original transporting member in said automatic transporting section is provided in an electrophotographic copying apparatus having an automatic paper original transporting section. Use of endless belts.