JPS61179347A - Reinforcement of bamboo material for knitting needle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" This invention relates to a method for reinforcing bamboo material for handicraft knitting needles.

``Prior Art'' Bamboo is considered the best material for knitting needles used in handicraft knitting because of its good usability. For knitting needles made of bamboo, there is no problem in terms of product strength if the raw material has a dense and hard texture, but if the raw material has a rough texture and poor strength, the product strength is unsatisfactory. .

However, sorting materials based on their strength not only leads to a significant increase in costs, but also increases the difficulty in obtaining materials.Therefore, there is a need for a method to strengthen raw materials so that they can be used uniformly regardless of the quality of the strength of the raw materials. As a means to solve this problem, methods of applying a natural or synthetic resin solution to the surface of the bamboo material, or immersing the material in the solution and then drying the material have been proposed and are currently in use.

``Problems to be Solved by the Invention'' However, in the above method, a resin coating is formed on the surface of the bamboo material, which only strengthens the surface strength, and the internal structure of the bamboo material remains almost the same. This was unsatisfactory as it was not possible to essentially improve the existing vulnerabilities.

"Means for Solving the Problems" The present invention effectively generates a strong synthetic resin component in the voids of the internal structure of bamboo material for knitting needles, strengthens the bamboo material from within the structure, and essentially improves its strength. This relates to a strengthening method aimed at improving the strength of bamboo material, in which bamboo material that has been previously formed into a round bar shape is placed in an appropriate container, and the air inside the container is sucked in with a vacuum pump to reduce the pressure inside the container to an appropriate degree of vacuum. , urea, formaldehyde, and ammonia in an appropriate ratio was sucked into the vacuum container, and the bamboo material was
The objective is to be achieved by heating in boiling water at 00°C for an arbitrary period of time and drying.

``Function'' In the present invention, after the bamboo material formed into a round rod shape is placed in a container, the air inside the container is sucked and depressurized using a vacuum pump, thereby also removing the air present in the voids in the internal structure of the bamboo material. Thereafter, a mixture of urea, formaldehyde, and ammonia in an appropriate ratio is sucked into the container, so that the mixture is quickly and reliably absorbed into the pores within the structure of the bamboo material. The above-mentioned mixed liquid does not react at normal temperature and normal pressure, but when heated, urea and formaldehyde undergo a polymerization reaction to produce urea resin. 80~1
After heating in hot water at 00℃ for several hours, and drying with air at 70 to 80℃, urea and formaldehyde in the bamboo structure are polymerized to produce urea resin. The fiber structure of the bamboo material is intertwined with the filled urea resin to strengthen the bamboo material from within the structure.

"Example" Bamboo material shaped into a round bar was placed in a suitably airtight container having an exhaust port and a solution inlet connected to a vacuum pump, and the pressure inside the container was reduced to a degree of vacuum of about 1 to 10 mm Hg using a vacuum pump. Ammonia was added as a catalyst to an aqueous solution mixed at a ratio of 1 mole of urea to 2 moles of formaldehyde to adjust the pH to about 8, and the mixture was sucked through the solution inlet of the container.

Afterwards, take out the bamboo material from the container, heat it in boiling water at 80-100℃ for 3-5 hours, and then blow air at 70-80℃.
゛After drying and complete drying, the product is made into a product through processes such as needle-forming, polishing, and head attachment. By efficiently producing urea resin, bamboo material can be essentially strengthened from within its structure.
Since it is possible to provide bamboo knitting needles that have a constant strength regardless of the quality of the raw materials, it is possible to save the trouble of material selection and to prevent the resulting increase in costs.

Claims (1)

[Claims] Bamboo material formed into a round rod shape of an appropriate thickness is placed in a container, and after reducing the pressure inside the container, a mixture of urea, formaldehyde, and ammonia in an appropriate ratio is sucked into the container, and the bamboo material is A method for strengthening bamboo material for knitting needles, which comprises heating in boiling water at 100°C for an arbitrary period of time and then drying.