CS233541B1 - Production method of writing fibre tips - Google Patents

Abstract

BACKGROUND OF THE INVENTION The present invention relates to a method of making writing instruments fiber tips. It is a writing thread spikes that are intended for writing instruments Known as marker and marker names The essence of the invention lies in the thermal pretreatment synthetic fibers, which will allow preservation crimping on the fibers and thereby achieving the desired porous structure and sufficient compactness writing fiber tips

Description

The invention relates to a method for producing writing fiber spikes. These are writing filament tips which are intended for writing devices known as markers or markers.

According to the prior art, in the manufacture of writing fiber spikes, a bundle of curled synthetic fibers is unwound from the unwinding stand and, after unwinding from the unwinding stand, passes under a specified tension through a tray with a solution of impregnating and binder thermosetting synthetic resin. The resin bundle saturated with the resin solution then passes through the heating zones upon exit from the tray, in which the resin solvent gradually evaporates and the resin cures. Because very dilute resin solutions are used and the synthetic fibers are crimped, the resin cures to form a thin layer of resin on the fibers, impregnating and fixing the curl and bonding the individual fibers together at the point of contact. This ensures the cohesion of the individual fibers in the synthetic fiber bundle, thereby ensuring the consistency and compactness of the entire bundle while maintaining its porosity. The compact yet sufficiently porous bundle of synthetic fibers is then further machined to the final dimension and shape of the writing fiber spikes. Thus, in order to achieve the desired function and quality of the writing fiber spikes, it is a condition that during the impregnation of the synthetic fiber bundle the curl on the individual fibers of the bundle is maintained and that the curl is not partially or completely damaged.

However, the prior art methods for producing writing fiber tips have a number of disadvantages. Since the synthetic fiber bundle is exposed to elevated stress and elevated temperature in the presence of organic solvents during the impregnation, the impregnation of the synthetic fiber bundle results in a partial and / or complete compensation of the curl of the synthetic fibers in the bundle , which negatively affects fiber cohesion, porosity, and the resulting writing properties of writing fiber tips, which have been produced by known methods.

These disadvantages are particularly pronounced in the manufacture of writing fiber spikes from polyester fibers. Since the polyester fiber has a low residual shaping effect, during the impregnation of the fiber bundle, the curl on the individual fibers of the bundle is completely equalized and the writing properties of the thus produced writing fiber tips are completely unsatisfactory.

These disadvantages are completely eliminated by the method of manufacturing the writing fiber tips of the invention. The essence of the invention is that before the actual impregnation, the bundle of curled synthetic fibers is heated to a temperature of 110 to 220 ° C and then cooled to a temperature at least 50 ° C lower.

The method for producing writing fiber spikes, the method of manufacture according to the invention, then exhibits a number of advantages and improvements.

It is ensured that the curls on the individual fibers of the synthetic fiber bundle are fully maintained, and that the curl is maintained during the impregnation of the bundle. This makes it possible to achieve the desired porosity of the impregnated bundle, while at the same time high bundle compactness. The writing fiber tips produced according to the invention exhibit very good writing properties. Without complicated and costly interventions in the technology, it is possible to produce writing fiber tips of various hardnesses, ranging from soft to medium hard to very hard, fine writing tips.

The invention is illustrated by the following examples.

Example 1

For the manufacture of a 2.0 x 30 mm writing fiber tip, a crimped polyester fiber having a unique fineness of 4.64 dtex is used. The polyester fiber is combined into a bundle having a total fineness of 22,717 dtex. A bundle of polyester fibers is not wound on a spool which is placed on a unwinding stand. The polyester fiber bundle is unwound from a coil and passes through heating zones in which it is heated to 220 ° C by hot air. Upon exiting the heating zones, the fiber bundle enters the tray with the impregnating and binder resin solution. The resin solution is allowed to warm to 20 ° C. By the action of the solution, the fiber bundle is cooled to 25 ° C. After exiting the tray, the resin-saturated bundle passes through the heating zones in which the resin cures. The impregnated polyester fiber bundle is then mechanically machined to the indicated dimension. In this way, writing fiber tips are made for use in water-based ink markers.

Example 2

A crimped polyester fiber having a fineness of 3.50 dtex was used to produce a 3.8 x 30 mm writing fiber tip. The polyester fiber is bundled into a bundle having a total fineness of 45,000 dtex. A bundle of polyester fibers is wound on a spool, which is placed on an opener stand. The fiber bundle is unwound from the coil and passes through a heating zone in which it is heated to 110 ° C by hot air. Upon exiting the heating zone, the fiber bundle is cooled to 60 DEG C. by the flowing air and then rewound the bobbin. The bobbin with the thus prepared bundle of threads is then allowed to warm to a temperature of 20 to 25 ° C for 24 hours. The impregnated bundle is then machined to the specified dimension. In this way, writing fiber spikes are made for use in a marker with fluorescent ink used for text highlighting.

Example 3

A crimped polyacrylonitrile fiber of one fineness of 3.00 dtex is used to produce a 2.0 x 30 mm writing fiber tip. The polyacrylonitrile fiber is bundled into a bundle having a total fineness of 25,200 dtex. The bundle of polyacrylonitrile fibers is wound on a spool, which is placed on a unwinding stand. The bundle of polyacrylonitrile fibers is unwound from a coil and passes through heating zones in which it is heated to 150 ° C by hot air.

Upon exiting the heating zones, the fiber bundle enters the tray with the impregnating and binder resin solution. The resin solution is allowed to warm to 20 ° C. By the action of the solution, the fiber bundle is cooled to 25 ° C. Upon exiting the tray, the saturated bundle passes through the heating zones in which the resin cures. The impregnated bundle of polyacrylonitrile fibers is then mechanically machined to the indicated dimension. In this way, writing fiber filaments are made for use in water-based ink markers.

Claims (1)

SUBJECT OF THE INVENTION Method for producing writing fiber tips from crimped synthetic fiber bundles which are subjected to impregnation and subsequent mechanical treatment, characterized in that, prior to impregnation, the crimped synthetic fiber bundle is heated to a temperature of 10 ° to 220 ° C and then cooled to at least 50 ° C lower.