JPH0729461B2 - ink ribbon - Google Patents

Description

TECHNICAL FIELD The present invention relates to an ink ribbon having good ink retention, clear printing and excellent durability.

(Prior Art) It is well known that an ink ribbon is used as a typewriter, a register and a computer ribbon.

Since such an ink ribbon transfers the ink in the ribbon to the printing paper by printing characters, synthetic fibers such as polyamide and polyester, which have large mechanical resistance to impact, are mainly used as the material. It's coming.

However, although the ink ribbon made of these synthetic fibers is superior in durability to conventional cotton and silk, it is inferior in ink holding property.

Therefore, it is not possible to sufficiently cope with high-speed printing of printers, which have been increasingly speeded up recently, and there is a long-awaited development of an ink ribbon that has good ink retention and printing clarity, and at the same time has excellent durability. Has been done.

(Problems to be Solved by the Invention) It is an object of the present invention to provide an ink ribbon having good ink retention properties, clear print quality, and excellent durability.

(Means for Solving Problems) The present invention has the following configuration in order to achieve the above object. That is, the ink ribbon of the present invention has a plurality of layered hollow portions in the fiber cross section, and at least a part of the hollow portions is made of a fabric composed of fibers having an opening communicating with the outside. Is.

FIG. 1 is a cross-sectional view showing an example of fibers constituting the ink ribbon of the present invention. An ink ribbon composed of this fiber has good ink holding property, printing sharpness and excellent durability due to the peculiarity of the fiber cross section.

In other words, since the fiber cross section has a plurality of layered hollow portions, a large amount of ink can be retained not only on the outside of the fiber but also inside the fiber, and when printed, the ink moves from the inside to the outside so that clear printing can be performed for a long time. It will be possible.

The opening that communicates with the outside of the fiber does not necessarily need to be continuous, and may have at least a gap into which ink enters and is pushed out by typing. From FIG. 1, this opening is not directly visible, but it is actually present.

The opening can be confirmed by cutting at least several points of the fiber in the direction orthogonal to the fiber axis direction and observing the section with a microscope.

In addition, since the fiber surface of the ink ribbon of the present invention has a continuous concavo-convex shape along the fiber axis, a woven fabric composed of such fibers has a structure in which adjacent fibers are strongly bound to each other and knitted. Since it is possible to prevent problems such as misalignment, perforation, and elongation of the woven fabric, it is possible to form a strong structure and obtain a durable ink ribbon.

The fiber forming the ink ribbon of the present invention is formed by assembling or laminating constituent elements having layered hollow portions having various shapes as shown in FIG. The shape of each of the constituent elements can be, for example, U-shaped, W-shaped, N-shaped, comb-shaped, or various shapes in combination thereof, and particularly if it has a layered hollow portion. It does not matter its shape. 2 to 4 show typical examples of the constituent elements of the fibers that form the ink ribbon.

The number of layered hollow portions present in the fiber is at least 2
4, preferably 10 or more, particularly preferably 20 or more. The larger the number of the hollow portions, the more the ink is likely to be contained, which is preferable. Therefore, it may be more than 1000 in some cases. The higher the ratio of the hollow portion in the fiber, that is, the higher the porosity, the larger the amount of ink that can be contained, but it is preferably 3% or more, particularly preferably 10% or more, but generally 1 to It is better to use 40%. Naturally, a large fiber surface area is also a feature of the present invention. The larger the fiber surface area, the easier it becomes to hold the ink on the fiber surface, which is preferable for improving the ink holding ability.

The surface area depends on the thickness of the fiber, but it is 1
If it is denier, 0.4 m ² / g or more is preferable, and 0.8 m ₂ / g or more is particularly preferable. If it is 10 denier, 0.2 m ² / g or more is preferable, and 0.4 m ² / g or more is particularly preferable.

This surface area includes the surface area of the outer circumference of the fiber and the area of the inner wall of the hollow portion.

Therefore, the fiber surface area S (m ² / g) is calculated by the following equation.

S = L × (A + B) where L: fiber length per gram A: fiber outer circumference length B: hollow inner wall total length A and B are cut 10 at right angles to the fiber axis Then, take a photograph of the cross section with a microscope and measure from the photograph to obtain the average value at 10 points.

The shape of the fiber surface is not specified, but the uneven shape is preferable.
That is, in order to make the woven fabric in the stamped portion less susceptible to stretching, misalignment, damage or the like, that is, in order to suppress wakame or waving phenomenon, it is preferable that the unevenness has a stepped angular shape. For that reason, it is preferable that the height of the unevenness is also high.

The present invention does not ask any means for producing such a fiber, but an example of producing such a fiber preferably is to spin a composite fiber having a cross section in which two kinds of polymers having different solubilities in a solvent are alternately bonded. A method in which one component is removed with a solvent before or after knitting or knitting into a knitted fabric is preferably a method in which a component having a layered hollow portion is joined during or after spinning.

The overall shape of the fiber cross section may be a circular cross section, but as shown in FIG. 1, a flat cross section fiber having a ratio of a major axis to a minor axis is particularly preferably used. The flat cross-section fiber may be linear or curved.

Examples of synthetic fibers applicable to the present invention include polyester fibers, polyamide fibers, polyacrylonitrile fibers, acetate fibers and the like. Polyamide fiber and polyester fiber are preferable as the polymer having a high mechanical resistance against the typed characters.

In the present invention, the ink ribbon is made of a knitted fabric formed by using the above fibers as warp or weft, and further as both warp and weft.

These yarns are generally 20 to 100 denier, preferably 30
Consists of ~ 70 denier multifilament yarn. The multifilament yarn generally has a denier of 1 to 5 and preferably 1 to 3 denier. A preferred example of such an ink ribbon knitted fabric is generally a warp yarn density of 15
A plain weave of 0 to 220 yarns / inch and weft yarn density of 100 to 150 yarns / inch is applied, but it is not necessary to be limited to this and any other yarn density or weave design may be used. I can't.

The ink ribbon is obtained by mixing the above-mentioned ink ribbon fabric with a colorant such as an organic or inorganic dye or pigment in water or another solvent and impregnating and / or applying 10 to 50 g of the ink per 1 m ^2. Created. The effects of the present invention are exerted without being affected by the type of the ink, and needless to say, are not limited to the above ink composition and application amount. In addition, it does not matter at all that a treatment for facilitating the ink to be contained in the woven fabric is performed in advance.

The obtained ink-coated fabric is cut into a predetermined width and length,
The ink ribbon is loaded on a predetermined reel or case.

(Examples) Hereinafter, the present invention will be described with reference to Examples, but the present invention is not limited to these Examples. Unless otherwise specified, "percentage" and "%" are based on weight.

Ink impregnation rate: After impregnating the fabric with the ink, squeezing it by applying a pressure of 1.0 kg / cm with a nip roller, the ink impregnation rate applied to the fabric Printing durability: Tokyo Electron Ltd. line printer model 4500 The ink ribbon was mounted on the test piece, and the ink-jet test was performed. The number of holes in the ink ribbon was limited. Example 1 Six pieces were connected in the vertical direction by using the fluid path forming pipeline structure described in JP-B-60-1048. Two spinning packs were installed in which a fluid mixer and an 18-hole spinneret with an orifice diameter of 1.0 mm were connected. A composite fiber in which 9 to 12 pairs of A and B composed of nylon 6 as the A component and polystyrene as the B component were alternately bonded repeatedly was melt-spun. The component ratio at this time is A / B
= 50/50.

Continue drawing speed 280m / min, heat pin temperature 120 ℃, draw ratio
Stretching was carried out at 3.2 to obtain a 75 denier, 18 filament yarn. The drawn yarn was twisted at 150 T / m as a warp yarn and 100 T / m as a weft yarn to woven a plain weave with a precision of 162 warps / inch and 105 wefts / inch.

This woven fabric was immersed in a treatment liquid containing a surfactant at 80 ° C. for relaxation scouring.

Then, B was removed by treating with trichlene as a solvent. The woven fabric was impregnated with an ink containing oleic acid and carbon black as main components. The amount of ink applied at this time was about 32 g / m ² . Further, it was cut along the warp thread to a width of 10 mm to obtain an ink ribbon. The performance of the thus obtained ink ribbon was compared with that of the conventional ink ribbon, and the results shown in Table 1 were obtained.

Comparative Example 1 An ink ribbon corresponding to a conventional product made in exactly the same manner as the conventional nylon 6 round cross-section yarn (40 denier / 18 filament) except for the triclin treatment.

As shown in the results of Table 1, the ink ribbon of the present invention has better ink retention than the conventional ink ribbon,
Furthermore, the printing clarity and durability were excellent.

(Effect of the Invention) The ink ribbon of the present invention has a layered hollow portion in the fiber, and part of the hollow portion is open to the outside of the fiber, so that a large amount of ink can be held in this hollow portion. . Therefore, the ink holding property is superior to that of the conventional ink ribbon. That is, unlike the conventional products, the ink existing outside the fiber has less dependence, and printing can be performed, so that clear printing can be performed for a long time.

Therefore, the ink ribbon of the present invention can sufficiently cope with the recent speedup of printers.

[Brief description of drawings]

FIG. 1 is a micrograph showing an example of a cross section of a fiber constituting the ink ribbon of the present invention. FIG. 2 to FIG. 4 are cross-sectional model diagrams showing one example of constituent elements constituting the fiber used in the present invention.

Claims (1)

[Claims] 1. An ink ribbon made of a fabric having a plurality of layered hollow portions in a fiber cross section, and at least a part of the hollow portions having an opening communicating with the outside.