Ultrafine bamboo fiber and method for preparing the same

Abstract

The application discloses a kind of superfine bamboo fiber and its preparation method, including steps: (1) bamboo is cut into bamboo block with length of 20-30cm, is placed in softening pool, and is cooked with alkaline solution, and bamboo block is softened and pre-degummed treatment;(2) using press roller, bamboo block after softening and pre-degumming is rolled and is treated with fiber, and bamboo coarse fiber is obtained;(3) bamboo coarse fiber after rolling is placed in degumming pool, and is cooked with lactic acid solution, and bamboo coarse fiber is degummed;(4) using drafting device, bamboo coarse fiber after degumming is drafted, and superfine bamboo fiber is obtained;(5) superfine bamboo fiber is bleached, oiled, and dried, and superfine bamboo fiber finished product is obtained.The application is cooked by alkali, pre-degummed, rolled and fibered, degummed by acid and drafted in cooperation, so that bamboo fiber is gradually degummed and fibered, thereby obtaining superfine bamboo fiber, and the quality of fiber is not damaged.

Description

Technical Field

[0001] This invention relates to the field of bamboo fiber preparation technology, specifically to an ultrafine bamboo fiber and its preparation method. Background Technology

[0002] Bamboo fiber is a plant fiber directly extracted from bamboo. It not only possesses excellent moisture absorption and quick-drying properties but also exhibits certain antibacterial properties, making it a desirable fiber raw material that meets modern needs. Due to the inherent characteristics of bamboo's plant growth, its fiber cells are densely aggregated, making it difficult to separate using conventional methods. Current methods for preparing bamboo fiber typically involve physically crushing bamboo and then cooking it with caustic soda. However, conventional caustic soda cooking yields relatively coarse fibers; industrially produced bamboo fiber can only achieve a maximum count of 500-600 metric counts, making further refinement difficult. While increasing the cooking intensity can refine the fibers, it also causes significant fiber damage, resulting in a substantial reduction in fiber strength and length, failing to meet the requirements of subsequent textile processing. Extracting ultrafine bamboo fiber from bamboo presents considerable challenges. However, ultrafine bamboo fiber can be used to produce high-end textiles. Based on this market demand, research into methods for preparing ultrafine bamboo fiber is urgently needed. Furthermore, the fineness of the bamboo fiber needs to reach at least 750 metric counts and a length of at least 30 mm to maximize its textile processing value. Summary of the Invention

[0003] To solve the above-mentioned technical problems, the present invention provides an ultrafine bamboo fiber and its preparation method. Through synergistic treatment of alkali boiling pre-degumming, rolling and fiber separation, acid degumming and stretching, the bamboo fiber is gradually degummed and separated to obtain ultrafine bamboo fiber without damaging the fiber quality.

[0004] The technical solution adopted in this invention is:

[0005] A method for preparing ultrafine bamboo fiber includes the following steps:

[0006] (1) Cut bamboo into bamboo blocks with a length of 20-30cm, place them in a softening tank, add an alkaline solution and steam them to soften and pre-degumme the bamboo blocks.

[0007] (2) Use pressure rollers to crush and separate the softened and pre-degummed bamboo blocks to obtain coarse bamboo fibers.

[0008] (3) Place the crushed bamboo coarse fiber in a degumming tank, add lactic acid solution for cooking, and degumm the bamboo coarse fiber.

[0009] (4) Use a stretching device to stretch the degummed bamboo coarse fiber to obtain ultrafine bamboo fiber;

[0010] (5) The ultrafine bamboo fiber is bleached, oiled and dried to obtain the finished ultrafine bamboo fiber product.

[0011] Furthermore, the alkaline solution in step (1) is a NaOH solution.

[0012] Furthermore, the concentration of the alkaline solution in step (1) is 5–20 g / L.

[0013] Furthermore, in step (1), the cooking temperature is 90-100℃ and the cooking time is 0.5-1.5h.

[0014] Furthermore, in step (2), the diameter of the bamboo coarse fiber is 30 to 3000 μm.

[0015] Furthermore, the concentration of the lactic acid solution in step (3) is 20-50 g / L.

[0016] Furthermore, in step (3), the mass ratio of bamboo coarse fiber to lactic acid solution is 1:10-20.

[0017] Furthermore, in step (3), the cooking temperature is 80-95℃ and the cooking time is 0.5-2h.

[0018] Furthermore, in step (4), the stretching ratio is 1.05 to 1.2 during the stretching process.

[0019] The present invention also provides an ultrafine bamboo fiber, which is prepared by the above preparation method, and the ultrafine bamboo fiber prepared has a fineness of 750-900 metric count and a length of 30-40 mm.

[0020] The present invention provides a method for preparing ultrafine bamboo fiber, which involves synergistic treatment of alkali boiling pre-degumming, rolling and fiber separation, acid degumming and stretching, so that the bamboo fiber is gradually degummed, separated and stretched, thereby obtaining ultrafine bamboo fiber with a fineness of 750-900 metric count and a length of 30-40 mm, without damaging the fiber quality. In the technical solution of this invention, on the one hand, bamboo blocks are softened and pre-degummed by alkaline boiling. The degree of pre-degumming can be controlled by controlling the concentration of the alkaline solution and the boiling time, preventing the alkaline boiling from causing severe damage to bamboo fiber cells (longitudinal separation and transverse breakage of fiber cells). Then, bamboo coarse fibers can be obtained by crushing and splitting, thus destroying the structural density of the bamboo itself. On the other hand, the bamboo coarse fibers after pre-degumming and crushing and splitting are subjected to lactic acid cooking treatment, which can hydrolyze the LCC bonds of cellulose, hemicellulose and lignin, and cause most of the hemicellulose to hydrolyze without affecting the cellulose itself. This weakens the interaction force between the fiber cells of bamboo fibers. Then, the degummed bamboo coarse fibers are subjected to low-intensity stretching treatment using a stretching device. The bamboo fibers can be slowly slid and displaced from the lactic acid hydrolyzed gum part by physical stretching, which can maximize the separation of bamboo fibers without damaging the fiber cells. During the stretching process, the bundled fibers can be stretched and displaced, and the fiber dispersion is more effective, thus obtaining ultrafine bamboo fibers.

[0021] Furthermore, it should be noted that in the above-mentioned technical solution of the present invention, alkaline boiling pre-degumming and mechanical rolling play an important role in the subsequent lactic acid degumming and low-strength stretching. Without alkaline boiling pre-degumming and mechanical rolling, due to the dense physical and biological structure of bamboo, lactic acid cannot directly act on the gum in the coarse fibers, but can only act on the surface of the bamboo, failing to separate the fibers and ultimately failing to obtain ultrafine bamboo fibers.

[0022] The beneficial effects of this invention are:

[0023] The present invention provides a method for preparing ultrafine bamboo fiber, which uses alkali boiling pre-degumming, rolling and fiber separation, acid degumming and stretching synergistic treatment to gradually degumm and separate bamboo fiber, which can separate the fiber in a green and efficient manner, making it easier to obtain finer bamboo fiber without damaging the fiber quality. Detailed Implementation

[0024] This invention provides a method for preparing ultrafine bamboo fiber. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0025] Example 1

[0026] This embodiment provides a method for preparing ultrafine bamboo fiber, including the following steps:

[0027] (1) Cut bamboo into 20cm long pieces, place them in a softening tank, add 10g / L of dilute NaOH solution, and steam at 100℃ for 1h to soften and pre-degumme the bamboo pieces.

[0028] (2) The softened and pre-degummed bamboo blocks are crushed and separated by pressure rollers to obtain coarse bamboo fibers with a diameter of 100-1000μm.

[0029] (3) Place the crushed bamboo coarse fiber in a degumming tank and add 30 g / L of lactic acid solution to make the bath ratio of bamboo coarse fiber to lactic acid solution 1:15. Then cook at 85℃ for 1 hour to degumme the bamboo coarse fiber.

[0030] (4) The degummed bamboo coarse fiber was stretched using a stretching device with a stretching ratio of 1.1 to obtain ultrafine bamboo fiber;

[0031] (5) The ultrafine bamboo fiber is bleached, oiled and dried to obtain the finished ultrafine bamboo fiber product.

[0032] The ultrafine bamboo fiber prepared in this embodiment was tested and found to have an average fineness of 813 metric counts and an average length of 35 mm.

[0033] Example 2

[0034] This embodiment provides a method for preparing ultrafine bamboo fiber, including the following steps:

[0035] (1) Cut bamboo into 20cm long pieces, place them in a softening tank, add 10g / L of dilute NaOH solution, and steam at 100℃ for 1h to soften and pre-degumme the bamboo pieces.

[0036] (2) The softened and pre-degummed bamboo blocks are crushed and separated by pressure rollers to obtain coarse bamboo fibers with a diameter of 100-1000μm.

[0037] (3) Place the crushed bamboo coarse fiber in a degumming tank and add 30 g / L of lactic acid solution to make the bath ratio of bamboo coarse fiber to lactic acid solution 1:15. Then cook at 85℃ for 1 hour to degumme the bamboo coarse fiber.

[0038] (4) The degummed bamboo coarse fiber was stretched using a stretching device with a stretching ratio of 1.2 to obtain ultrafine bamboo fiber;

[0039] (5) The ultrafine bamboo fiber is bleached, oiled and dried to obtain the finished ultrafine bamboo fiber product.

[0040] The ultrafine bamboo fiber prepared in this embodiment was tested and found to have an average fineness of 883 metric counts and an average length of 32 mm.

[0041] Example 3

[0042] This embodiment provides a method for preparing ultrafine bamboo fiber, including the following steps:

[0043] (1) Cut bamboo into 30cm long pieces, place them in a softening tank, add 20g / L of dilute NaOH solution, and steam at 90℃ for 1.5h to soften and pre-degumme the bamboo pieces.

[0044] (2) The softened and pre-degummed bamboo blocks are crushed and separated by pressure rollers to obtain coarse bamboo fibers with a diameter of 50-800 μm.

[0045] (3) Place the crushed bamboo coarse fiber in a degumming tank and add 50 g / L of lactic acid solution to make the bath ratio of bamboo coarse fiber to lactic acid solution 1:20. Then cook at 93℃ for 0.5 h to degumm the bamboo coarse fiber.

[0046] (4) The degummed bamboo coarse fiber was stretched using a stretching device with a stretching ratio of 1.05 to obtain ultrafine bamboo fiber.

[0047] (5) The ultrafine bamboo fiber is bleached, oiled and dried to obtain the finished ultrafine bamboo fiber product.

[0048] The ultrafine bamboo fiber prepared in this embodiment was tested and found to have an average fineness of 785 metric counts and an average length of 39 mm.

[0049] Comparative Example 1

[0050] This comparative example provides a method for preparing ultrafine bamboo fiber, including the following steps:

[0051] (1) Cut bamboo into 20cm long pieces, place them in a softening tank, add 10g / L of dilute NaOH solution, and steam at 100℃ for 1h to soften and pre-degumme the bamboo pieces.

[0052] (2) The softened and pre-degummed bamboo blocks are crushed and separated by pressure rollers to obtain coarse bamboo fibers with a diameter of 100-1000μm.

[0053] (3) Place the crushed bamboo coarse fiber in a degumming tank and add 30 g / L of lactic acid solution to make the bath ratio of bamboo coarse fiber to lactic acid solution 1:15. Then cook at 85℃ for 1 hour to degumme the bamboo coarse fiber.

[0054] (4) The degummed bamboo coarse fibers are bleached, oiled and dried to obtain fine bamboo fiber finished products.

[0055] The fine bamboo fibers prepared in this comparative example were tested, and their average fineness was 430 metric counts and their average length was 57 mm.

[0056] Comparative Example 2

[0057] This comparative example provides a method for preparing ultrafine bamboo fiber, including the following steps:

[0058] (1) Cut bamboo into 20cm long pieces, place them in a degumming tank, and add 30g / L of lactic acid solution to make the ratio of bamboo coarse fiber to lactic acid solution 1:15. Then cook at 85℃ for 1h to degumming process to obtain bamboo coarse fiber with a diameter of 500~2000μm.

[0059] (2) The degummed bamboo coarse fiber was stretched using a stretching device with a stretching ratio of 1.1;

[0060] (3) The bamboo fiber after stretching is bleached, oiled and dried to obtain the finished bamboo fiber product.

[0061] The bamboo fiber prepared in this comparative example was tested and found to have an average fineness of 215 metric counts and an average length of 86 mm.

[0062] Comparative Example 3

[0063] This comparative example provides a method for preparing ultrafine bamboo fiber, including the following steps:

[0064] (1) Cut the bamboo into 20cm long pieces, place them in a softening tank, and put the bamboo fibers into 100℃ hot water for 1 hour to soften them.

[0065] (2) Use pressure rollers to crush and separate the softened and pre-degummed bamboo blocks to obtain coarse bamboo fibers.

[0066] (3) Place the crushed bamboo coarse fiber in a degumming tank and add 40g / L NaOH solution to cook at 100℃ for 2.5h to degumme the bamboo fiber.

[0067] (4) The degummed bamboo fiber is bleached, oiled and dried to obtain the finished bamboo fiber product.

[0068] The bamboo fiber prepared in this comparative example was tested and found to have an average fineness of 539 metric counts and an average length of 38 mm.

[0069] Comparative Example 4

[0070] This comparative example provides a method for preparing ultrafine bamboo fiber, including the following steps:

[0071] (1) Cut the bamboo into 20cm long pieces, place them in a softening tank, and put the bamboo fibers into 100℃ hot water for 1 hour to soften them.

[0072] (2) Use pressure rollers to crush and separate the softened and pre-degummed bamboo blocks to obtain bamboo fibers;

[0073] (3) Place the crushed bamboo coarse fiber in a degumming tank and add 100g / L NaOH solution to cook at 100℃ for 3h to degumme the bamboo fiber.

[0074] (4) The degummed bamboo fiber is bleached, oiled and dried to obtain the finished bamboo fiber product.

[0075] The bamboo fiber prepared in this comparative example was tested and found to have an average fineness of 762 metric counts and an average length of 16 mm.

[0076] It should be noted that any parts not mentioned in this invention can be achieved by using or referencing existing technologies.

[0077] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for preparing ultrafine bamboo fiber, characterized in that, Includes the following steps: (1) Cut bamboo into pieces with a length of 20-30cm, place them in a softening tank, add an alkaline solution and steam them to soften and pre-degumme the bamboo pieces. (2) The softened and pre-degummed bamboo blocks are crushed and separated into coarse bamboo fibers by using pressure rollers; (3) Place the crushed bamboo coarse fiber in a degumming tank, add lactic acid solution for cooking, hydrolyze the LCC linkage of cellulose, hemicellulose and lignin, and degumm the bamboo coarse fiber. (4) Use a stretching device to stretch the degummed bamboo coarse fibers to obtain ultrafine bamboo fibers; (5) Bleaching, oiling and drying the ultrafine bamboo fiber to obtain the finished ultrafine bamboo fiber product; The concentration of the lactic acid solution in step (3) is 20~50g / L; In step (3), the mass ratio of bamboo coarse fiber to lactic acid solution is 1:10~20; In step (3), the cooking temperature is 80~95℃ and the cooking time is 0.5~2h; In step (4), the stretching ratio is 1.05 to 1.2 during the stretching process. The fineness of the ultrafine bamboo fiber is 750~900 metric count, and the length is 30~40mm.

2. The method for preparing ultrafine bamboo fiber according to claim 1, characterized in that, In step (1), the alkaline solution is a NaOH solution.

3. The method for preparing ultrafine bamboo fiber according to claim 1, characterized in that, The concentration of the alkaline solution in step (1) is 5~20g / L.

4. The method for preparing ultrafine bamboo fiber according to claim 1, characterized in that, In step (1), the cooking temperature is 90~100℃ and the cooking time is 0.5~1.5h.

5. The method for preparing ultrafine bamboo fiber according to claim 1, characterized in that, The diameter of the bamboo coarse fiber in step (2) is 30~3000μm.