TW201942444A - Pulp and lyocell articles with reduced cellulose content - Google Patents

Abstract

The present invention describes special cellulose compositions that allow a lyocell fibre with a reduced cellulose content to be produced on a stable industrial scale, as well as the lyocell fibre produced from it.

Description

Wood pulp and lycra articles with reduced cellulose content

The present invention describes a special cellulose composition capable of stably producing Lycium fiber with reduced cellulose content on a large scale, and Lycium fiber made from it.

Lycra fibers are used in a variety of applications. Purified cellulose is often used as a raw material, with very small proportions of different final parts made from cellulose.

Wood pulp is obtained from wood consisting of only 40 to 44% by weight cellulose. As wood pulp used in the manufacture of nylon fiber molded products generally requires a high cellulose content of more than 95% by weight, the raw materials used for funding materials will lose most of them during cooking and bleaching. There are many known ways to reduce the hemicellulose ratio, whether it is from wood to wood pulp or to the production of the final fiber pulp:
a) Digestion: Most hemicellulose is lost during sulfite cooking, while in alkaline digestion, hemicellulose is removed by prehydrolysis before cooking.
b) Bleaching: Usually used to remove residual lignin and / or optical whitening, but also destroys the hemicellulose component
c) Partial insolubility of the branched hemicellulose part in the fiber solvent
d) Degraded in the spinning dope and then dissolved in the spinning bath.

There are indeed efforts to treat these other components as by-products. However, due to known technical limitations, only a few have been implemented. In waste liquor from wood pulp manufacture, in addition to being mixed with strong acids or alkalis, these additional wood components are present in the form of a large number of different degradation products, which makes separation and further processing very difficult. WO 98/16682 describes a method for producing a cellulose composition suitable for use in the manufacture of fibers. The starting mixture, which is deemed unsuitable for fiber manufacturing (but only for paper manufacturing), is processed to reduce the hemicellulose content, especially the xylan content. WO 99/47733 describes many lyocell fibers and WO 2010/132151 A2 discloses a wood pulp with a low degree of polymerization of cellulose.

However, in recent years, efforts have been made to broaden the raw material base of Lycra fiber products by using cellulose with incremental lignin and / or hemicellulose. US 6440523 and US 6444314 describe such methods as examples:

The method used in these papers is basically describing wood pulp and / or lye fiber products made therefrom, which in addition to this cellulose content also has a hemicellulose content of more than 5% by weight. However, Xian believes that in all of these works, the higher hemicellulose content described can be achieved only if many other basic conditions are met at the same time. These are, for example, a certain viscosity of the wood pulp, a maximum copper number and / or a maximum k number.

Although Lycra products are described in these papers, it is worth noting that the development based on these intellectual property rights has not been achieved on a large scale. However, the special use of cellulose with a higher hemicellulose content will bring significant costs and thus competition. Strength advantage. This may be due to the difficulty in expanding from laboratory scale and achievable fiber properties, which is not in line with expectations in the textile and non-woven markets. US 2015/0184338 A1 discloses wood pulp with a low content of hemicellulose.

The task of the invention

In order to maximize the use of resources, I want to be able to use as many material components as possible from this raw wood to make fiber. The main goal in the search for the most comprehensive sustainability and truly effective concept of biorefinery must be from the beginning as much as possible the main product, in other words the fiber-formed body, using wood from natural raw materials in a comprehensive way. Extraction of by-products is still very important, but overall it remains secondary. Previous efforts to achieve this have failed because the reduced cellulose content in the fiber caused a drastic change in the material and property parameters of the resulting (rayon) fiber (or other variant of the molded body), or another On the other hand, stable large-scale production cannot be achieved. On the contrary, a large number of patents and publications require that the content of lignin, hemicellulose and auxiliary components should be extremely low for the large-scale application of chemical wood pulp in the Lycra method.

For these reasons, what I want to provide is a technology that can be used on a large scale. By increasing the proportion of other wood components, especially hemicellulose and lignin, to reduce the proportion of cellulose in the finished fiber, There are no major restrictions on the material parameters. Although there are many state-of-the-art methods, there is currently no known method that can be used on a large scale to make this fiber product with reduced cellulose content.

The present invention overcomes the problems of the aforementioned prior art. The present invention provides a wood pulp such as those in the scope of the patent application, a fiber product such as the scope of the patent application, and a method in the scope of the patent application. The preferred forms of the invention are specified in the appended items and the following detailed description of the invention.

In particular, the present invention provides the following aspects, as well as preferred specific examples cited in the attached items and the description.
1. A wood pulp suitable for manufacturing a fiber-formed body, having a cellulose content of 90% by weight or less, preferably 85% by weight or less, and a hemicellulose content of at least 7% by weight, the wood The pulp is characterized in that the ratio of C5 / xylan to C6 / mannan moiety (C5 / C6 ratio) existing in the hemicellulose is in a range of 125: 1 to 1: 3.
2. The cellulose of specific example 1, wherein the C5 / C6 ratio is in the range of 25: 1 to 1: 2.
3. The wood pulp according to the specific examples 1 and / or 2, wherein the proportion of the hemicellulose is 10% by weight or more.
4. The hemicellulose of at least one of the above specific examples exists in a natural state, has been chemically modified through a processing process, or has been chemically modified or functionalized in a separate process step.
5. The wood pulp according to at least one of the above specific examples, which has a lignin content higher than 1% by weight.
6. The wood pulp according to at least one of the above specific examples, wherein the cellulose content is further reduced due to the presence of lignin, ancillary components and / or addition of metal compounds from the wood.
7. The wood pulp according to at least one of the above specific examples, which has a xylan content of 9% by weight or more and / or a mannan content of 6% by weight or more.
8. The wood pulp of specific example 7, which has a xylan content of 9% by weight or more and a mannan content of 1% by weight or less.
9. A fiber-formed body produced by using a wood pulp as described in any one of specific examples 1 to 8.
10. The lyocell shaped body according to the specific example 9, wherein the forming system is selected from the group consisting of fibers, filaments, staple fibers, nonwoven knits, films, and spherical powders.
11. The lyophilized fiber shaped body according to at least one of the specific examples 9 and / or 10, wherein the forming system fiber, filament or short fiber has a cellulose content of less than 90% by weight and a fiber content of more than 5% by weight Hemicellulose content and a C5 / C6 ratio of 125: 1 to 1: 3, preferably 25: 1 to 1: 2.
12. The fiber-reinforced molded article according to at least one of the specific examples 9 to 11, wherein the hemicellulose content is higher than 10% by weight.
13. The fiber-formed article according to at least one of the specific examples 9 to 12, wherein the forming system has a WRV fiber, filament or more than 70%, preferably more than 75%, especially more than 80%. short fibre.
14. The fiber-formed article according to at least one of the specific examples 9 to 13, wherein the formed article has a crystallinity of 40% or less.
15. The lyocell shaped body according to at least one of the specific examples 9 to 14, which has a lignin content higher than 0% to 5% by weight.
16. A method for manufacturing a fiber-formed body, comprising dissolving a wood pulp having a cellulose content of 90% by weight or less, more preferably 85% by weight or less, and a hemicellulose content of at least 7% by weight, It is characterized in that the ratio of C5 / xylan to C6 / mannan (C5 / C6 ratio) stored in the hemicellulose is in a range of 125: 1 to 1: 3 in a suitable solvent, and The solution was formed into a formed fiber.
17. The method according to the specific example 16, wherein the fiber forming system is obtained by a fiber spinning process.
18. A method of manufacturing wood pulp according to any one of the specific examples 1 to 8, the aforementioned method comprises at least one of the following steps:
a) mixing pure wood pulp with xylan and / or mannan;
b) chemically and / or physically treating wood pulp having a hemicellulose content including mannan to change the hemicellulose content and / or hemicellulose composition contained therein;
c) Use of coniferous and / or deciduous wood to make wood pulp;
d) mixing wood pulp without mannan with hemicellulose-rich wood pulp, and optionally chemically and / or physically treating the mixture thereafter to adjust the hemicellulose content and / or The composition of the hemicellulose part;
e) mixing two wood pulps having different hemicellulose content and / or hemicellulose composition, and thereafter chemically and / or physically treating the mixture as necessary to adjust the hemicellulose content and / or the hemicellulose Composition of cellulose part.
19. The method of embodiment 18, wherein the different wood pulps are selected from wood pulps with hardwood and softwood as substrates.

If the proportion of cellulose is reduced during the processing of Lycra, this means that the savings will be offset by other substances in the wood raw material. As mentioned above, when the cellulose content is reduced, this brings problems of process stability or property change. The main component of the non-cellulosic material in the raw wood is hemicellulose (basically a polysaccharide selected from the sugar monomers xylose, arabinose, mannose, galactose, glucose and rhamnose), lignin and ancillary ingredient.

Cellulose: It is a structural material of the wood cell wall, mainly used for tensile strength. The long molecular chains of glucose units are stored together in the form of so-called fibrils, which are multiples of the helical structure. This helical arrangement in the cell wall ensures good bending strength of the tree, such as in the case of wind loads or in the case of, for example, the wood of a roof building. Cellulose is hydrophilic, but not water-soluble due to its high crystallinity.

Lignin: A binder for solid adhesion of cellulose in the form of an amorphous matrix. Therefore, lignin is mainly responsible for compressive strength. On the other hand, lignin has poor flexibility and is hydrophobic in contrast to cellulose. It is responsible for the support of the tree. Plants that do not store lignin only reach low growth heights. Lignin is relatively biologically stable and can only be slowly biodegraded.

Hemicellulose in the present invention means a component that is present in wood as a short-chain polymer of C5 and / or C6 sugars. Compared to cellulose, it has pendant groups and can therefore only form crystals to a much smaller extent. The basic building blocks are mannose, xylose, glucose, rhamnose and galactose. The pendant group preferably consists of arabinose, acetamyl, and galactose residues, as well as O-acetamyl and 4-O-methylglucuronic acid side groups. It is known that mannan prefers to bind to cellulose, while xylan easily binds to lignin. The composition of hemicellulose varies greatly depending on the type of wood used. During the manufacture of wood pulp, the side chains are partially separated and the polymer chains are split. In the context of the present invention, the wording hemicellulose includes those in their natural structure and those that are altered by their processing, as well as those that otherwise adjust their intended use by specific chemical modifications. Also included are short-chain cellulose and other polyoses with DP up to 500.

Ancillary components: Ancillary constituents are organic and inorganic wood components other than lignin, cellulose and hemicellulose, and usually include salts and low molecular organic compounds up to about 100 atoms, such as tannin, resin , Fats and waxes, tannins and humics, terpenes, terpenoids and phenols, pectin, suberin, polyphenols and polysaccharides.

If the cellulose content in the cellulosic material is reduced as required and this decrease is compensated by other components of the raw wood, it surprisingly shows that only certain combinations of different types of sugars are likely to show a certain cellulose, Although their cellulose content is reduced, they can be safely manufactured on a large scale, so that these products also have a reduced cellulose content, but still have satisfactory product performance.

According to the present invention, the reduced cellulose content in substantially less than 90% by weight of wood pulp has a hemicellulose content of at least 7% by weight, sugars having five carbon atoms (such as xylan) and sugars having six carbon atoms The ratio (for example, mannan) (hereinafter referred to as the C5 / C6 ratio) is in the range of 125: 1 to 1: 3.

Surprisingly, even if the content of cellulose in the wood pulp is reduced, the large-scale production of nylon fiber products can be safely achieved with the wood pulp.

The fiber material used herein, which is preferred by the user in the context of the present invention, has, as already explained, a relatively high content of hemicellulose having a composition as defined herein. Compared to standard wood pulps with a low hemicellulose content, and especially in the prior art for the production of standard lycra fibers, the preferred wood pulps used in the context of the present invention also show other differences as listed below.
Compared to standard Lycra materials, the Lycra materials that are preferably used in the present invention exhibit a rather fluffy appearance. After milling (during the manufacture of the starting material for the spinning solution used in the process of making fiber), this will result in a high proportion of the particle size distribution of the larger particles. As a result, the bulk density is much lower than standard wood pulp with a low hemicellulose content. This low overall density must comply with the dosing parameters (eg using at least two storage tank dosing) during the manufacture of the spinning solution. In addition, the nylon fiber material that is preferably used in the present invention exhibits the immersion characteristics to NMMO, and here it is more difficult to impregnate than the standard nylon fiber material. This can be detected by evaluating the impregnation properties according to Cobb's estimation. Although the Cobb value of standard wood pulp is usually greater than 2.8 g / g (according to DIN EN ISO 535, measured in accordance with a 78% NMMO aqueous solution at 75 ° C plus a 2-minute immersion time), the wood used in the present invention is preferably The pulp however showed a Cobb value of about 2.3 g / g. This requires adjustments during the preparation of the spinning solution, such as increased dissolution time (e.g. as explained in WO 94/28214 and WO 96/33934) and / or temperature adaptation and / or increased shear during dissolution (e.g. WO 96 / 33221, WO 98/05702 and WO 94/28217). This makes it possible to produce a spinning solution that allows the wood pulp described herein to be used in a standard fiber spinning process.

In a preferred form of the present invention, the wood pulp used to make the fiber product, preferably the fiber as described herein, is shown at 300 to 440 ml / g, especially 320 to 420 ml / g, more preferably SCAN viscosity in the range of 320 to 400 ml / g. The scanning viscosity is measured according to SCAN-CM 15:99 using a cupriethylenediamine solution. This method is known to experts and can be performed with commercially available devices, such as commercially available from PSL-Reotek Auto PulpIVA PSLRheotek device. This scanning viscosity is an important parameter that affects the processing of wood pulp during the manufacture of spinning solutions. Even though Erwood pulp shows high consistency in composition and so on, different scanning viscosities will lead to completely different performance during processing. In a direct dissolution spinning process such as the Lycra process, the wood pulp is dissolved in NMMO as it is. Compared with the viscose process, for example, there is no ripening step, in which the degree of polymerization of the cellulose can be adjusted according to the needs of the process. Therefore, the viscosity specification of the raw wood pulp is usually within a small target range for the fiber processing process. Otherwise, problems may occur during manufacturing. According to the present invention, it has been found that the viscosity of the wood pulp is preferably as described above. The lower viscosity can compromise the mechanical properties of the fiber product. In particular, higher viscosities lead to an increase in the viscosity of the spinning solution, and therefore the entire spinning becomes slower. Slower spinning speeds also result in lower tensile ratios, which can also have a significant impact on the fiber structure and fiber properties (Carbohydrate Polymers 2018, 181, 893-901). This will require program adjustments that will result in reduced capacity. On the one hand, the use of cellulose with a viscosity as defined herein enables simple processing and manufacturing of high-quality products.

As used herein, the terms "fabrication process" or "fabrication technology" and "fabrication process" refer to cellulose wood pulp or other cellulose-based raw materials in a polar solvent (such as N-methylmorpholine) N-oxide (NMMO, NMO) or ionic liquid). Commercially, this technology is used to make a series of cellulosic staple fibers (commercially available from Lenzing AG, Lenzing, Austria under the registered trademark TENCEL® or TENCEL ™), which are widely used in the textile or non-woven industry. Other cellulose shaped bodies made by Lycra technology have also been manufactured. According to this process, the cellulose solution is usually extruded using a molding machine in a so-called dry-wet spinning process and a shaped solution is obtained, for example, after entering the precipitation bath through an air gap, where it is obtained by precipitating the cellulose Shaped body. After going through further processing steps, the molded article is washed and dried if necessary. The process for making Lycra fibers is described, for example, in US 4246221, WO 93/19230, WO 95/02082 or WO 97/38153. Until the present invention discusses the disadvantages associated with prior art and discusses the unique properties of the new products disclosed and claimed herein, especially in the context of using laboratory equipment (especially in prior art) or in (semi-industrial) In the context of a pilot plant and a commercial fiber spinning unit, the present invention should be understood to mean a unit that can be defined in terms of its production capacity as follows:
Semi-industrial pilot plant: about 1 kt / a
Industrial equipment greater than 30 kt / a

In the context of the present invention, it has been shown that, particularly during the manufacture of fibers with a background of a lycra process, the orientation of the fiber manufacturing and drawing directions will occur. From the initial more or less non-oriented mixture of different polymers and other components in the spinning dope, the strong narrowing of the cross-section at the spinneret results in the initial orientation of the polymer in the manufacturing direction. Additional stretching in the air gap after passing through the spinneret and during subsequent processing steps results in a stretch-oriented fiber structure of the polymer. These processes are well known in the professional literature.

The fiber properties are strongly influenced by the type and composition of the polymer. It is also known that cellulosic fibers made by the lycra process have a very high crystallinity of about 44 to 47%, and fibers from the rubber yarn process have a crystallinity of about 29 to 34%. The crystallinity describes the orientation of the cellulose polymers relative to each other, and thus, for example, their ability to absorb, swell, and store water. In addition, the polymer chains in the non-crystalline region of the spun fiber are more ordered than the polymer chains in the rayon fiber. As a result, ordinary lycra fibers swell less and are less suitable for high-absorbent products than rayon fibers.

The use of cellulose with a reduced cellulose content according to the invention unexpectedly makes possible a completely different type of agglomeration of the polymer and thus a different structure of the fiber. Its crystallinity is significantly lower, typically 40% or lower, such as 39% or lower, for example 38% to 30%, such as 37% to 33%.

The WRV value of the fiber according to the present invention is separated or combined with other preferred designs described herein, preferably in combination with the crystallinity value of the fiber described herein, preferably 70% or higher, especially 75% or Higher, such as 80% or higher, such as from 70% to 85%.

It is known from the literature that if the side chains of the xylan are separated during the manufacturing process and precipitated from the pure xylan solution, then xylan will also form a crystal structure (Fengel, Wegener p. 113; Fengel D, Wegener G (1989): Wood, Chemistry, Ultrastructure, Reactions; Walter de Gruyter Verlag). The same applies to Mannan (ibid .; p. 119). However, in the present invention, the opposite effect can be seen. The polymer including the cellulose is stored in the spinning dope as a mixture, and is therefore also spun out and precipitated. Furthermore, the hemicellulose still has side groups because the glucuronic acid side groups of the xylan are relatively stable under acid digestion conditions (Sixta H (Ed.) (2006): Handbook of Pulp Vol. 1; Wiley VCH p. 418). The hemicellulose therefore meets all the conditions required to disrupt the crystallization of the cellulose, thereby forming a more disordered structure than standard Lycra fibers. Therefore, experts expect that higher hemicellulose content and reduced cellulose content will result in useless products, especially fibers. However, it was unexpectedly shown that the hemicellulose content in combination with the C5 / C6 ratio can be used to selectively control product properties. This mixture of different sugar polymers still achieves a crystallinity value higher than that of the rayon fiber, but now the fiber's overall accessibility to water has increased, so the water retention capacity (WRV) can be significantly improved. This improved absorbency is a decisive advantage for various applications, such as non-wovens. The relationship between this reduction in crystallinity and the improvement of the water retention capacity of the fiber is shown in FIG. 1 and can be adjusted by reducing the cellulose content in the fiber as described above.

As shown in the examples, the quality of Sinlay fiber with reduced cellulose content is similar to conventional TENCEL® fiber. It is clear that the fiber strength is slightly lower than TENCEL® fiber, measured in the examples as strength and working capacity. At the same time, the cellulose content may be significantly reduced, which is reported as a glucan value in the examples. By absorbing other wood components, the crystallinity is reduced by up to 21%, and the absorbency is significantly increased by up to 27%, measured in the examples as the crystallinity index and water retention capacity. Interestingly, the crystallinity of the Sinclair fiber according to the present invention is between conventional TENCEL® fiber and non-woven Lenzing Viscose® fiber; meanwhile, the WRV is in the range of Lenzing Viscose®. The WRV is therefore increased more strongly than can be explained by a decrease in the crystallinity of the fiber. This is a clear sign of unexpected characteristics that can be achieved with the present invention. Other components such as, in particular, hemicellulose, and lignin and ancillary components from wood not only provide a significant increase in yield, that is, improved sustainability, but also a significant improvement in product performance, such as water retention capacity.

Concrete example

As defined in item 1 of the scope of the patent application, the wood pulp according to the invention is characterized by a reduced cellulose content, a minimal amount of hemicellulose and a certain C5 / C6 ratio relative to the composition of the hemicellulose.

In a preferred form, the wood pulp, which can also be a mixture of different wood pulps (as long as the basic conditions are met), has 7 to 50% by weight, preferably 7 to 30% by weight, and more preferably 15 to 25. % By weight, for example wood pulp with a hemicellulose content of 10 to 20% by weight.

The wood pulp used according to the present invention is also preferably a wood pulp containing at least 9% by weight of xylan, more preferably at least 10% by weight of xylan. As long as the ratio defined in the present invention is satisfied, the ratio of the mannan can be combined or independently selected within a wide range. Suitable mannan content is in the range of 0.1 to 10% by weight, such as 0.1 to 9% by weight, and 0.1 to 6% by weight, 0.1 to 4% by weight, 5 to 10% by weight, 6 to 10% by weight, 0.1 to 9% by weight and so on. In an embodiment, the mannan content is in the range of 0.1 to 1% by weight, preferably in combination with at least 9% by weight, preferably at least 10% by weight of xylan content. In other designs, the manganese content is higher, preferably in the range of 6% by weight or more.

In a preferred form, separated from or combined with the form described above and below, the cellulose content of the wood pulp is in the range of 90% to 50% by weight, preferably 90% to 60% by weight. In the range of, for example, 85% to 70% by weight.

The weight ratio of the cellulose to the hemicellulose may be between 1: 1 and 20: 1. The proportion of the accessory component may be more than 0.05% by weight, preferably more than 0.2% by weight, and more preferably more than 0.5% by weight. Surprisingly, it has been shown that with this proportion of ancillary components in the wood pulp according to the present invention, the C5 / C6 ratio in the manufactured fiber products, especially fibers, is supported and the semi There was no significant change in the cellulose content (i.e. the content in the fiber product was not reduced or only reduced to a small extent compared to the wood pulp).

In another preferred design, the C5 / C6 ratio according to the present invention achieves such a high water retention capacity, while at the same time allowing a metal compound ratio of up to 25% by weight based on the weight of the fiber product, which is usually based on its oxide And the existence of hydroxide forms (for example, Mg (OH) ₂ or Al (OH) ₃ for flame retardant purposes), which makes it possible to further substantially reduce the cellulose ratio. This metal compound is especially TiO ₂ , Al ₂ O ₃ , MgO, SiO ₂ , CeO ₂ , Mg (OH) ₂ , Al (OH) ₃ , BN, ZnO, and part of the mineral components from wood may be added to the fiber It is used as a functional additive (flame retardant, matting agent, bactericidal ...) in the vegetarian solution.

In another preferred design, lycra fibers with a cellulose content of less than 70% can be manufactured, which not only meets the actual requirements (mechanical strength, etc.) compared to known lycra fibers, but also because of the invention The resulting new features are more suitable for certain applications. Relevant research has shown that the fibers in the proposed composition particularly show improved water retention and rapid biodegradability during composting.

According to the present invention, it has been shown that the C5 / C6 sugar ratio of the non-cellulosic polymer is an important factor in regulating the fiber composition and its resulting properties. By adjusting this ratio, combined with the hemicellulose content, the desired product properties can be adjusted.

In this case, experts know how to control or adjust the C5 / C6 ratio. This can be achieved by mixing various wood pulps such as soft wood pulps with higher mannan content and hard wood pulps with higher xylan content. Tests have proven another very effective way to adjust settings. The C5 to C6 sugar ratio can be controlled by setting specific cooking parameters such as the H factor. This is illustrated in Figures 2 and 3. This H factor is considered to be a necessary parameter for controlling sulphite cooking (Sixta (Vol. 1 2006) p. 432). It summarizes the cooking temperature and cooking time into one specification.

Figure 2 shows the effect of H factor on the ratio of hemicellulose in hardwood when sulphite is boiled using beech as an example. The content of xylan in hardwood is naturally higher. With the increase of H factor, xylan was degraded more than mannan. The ratio C5 / C6 is reduced.

When using softwood, this hemicellulose ratio is another way. Higher proportions of mannan in wood and wood pulp. Here, contrary to expectations, as shown in Figure 3, mannan breaks down faster than xylan.

Another way to adjust the wood pulp composition according to the present invention is to add C5 and / or C6 sugars previously obtained in other processes or process steps, such as alkali extraction, cold alkali extraction or E-step and the like. For the production of rayon fibers, it is known to add hemicellulose in a dissolved form to the spinning material and thereafter to perform joint spinning (WO2014086883). This makes it possible to produce viscose fibers having a reduced cellulose content. This is only possible because the process of gelatin yarns takes place in an aqueous medium and the hemicellulose is correspondingly alkali-soluble, so cellulose xanthate and dissolved hemicellulose can be mixed together And spin together. In contrast, the wood pulp is dissolved in NMMO or similar solvents during the process of the fiber, which means that no alkaline or aqueous solution can be added. It will dilute the solvent and reduce solubility or even cause unwanted precipitation. Therefore, hemicellulose cannot be added as a solution when manufacturing a spinning solution, but the process must be introduced in a different way. One possibility is to add during the wood pulp manufacturing process, so the mixture can then be dried with the wood pulp.

Surprisingly, it has been found that paying close attention to the hemicellulose composition is a key point in the technical manufacturing of nylon fiber molded products, especially fibers. Only when the proportion of the C5 part is related to the proportion of the C6 part, can hemicellulose be used on a large scale in the fiber structure. The ratio of the xylan to the mannan is preferably between 18: 1 and 1: 3, and more preferably between 9: 1 and 1: 2. At the same time, this mixing ratio allows 0.5 to 5% by weight of lignin (and / or other accessory components) to be added to the fiber structure without compromising desired properties to an unfavorable degree.

The fibers provided by the present invention have common fiber deniers, such as 7 dtex or lower, for example 2, 2 dtex or lower, such as 1, 3 dtex or lower, or even lower, such as 0.9 dtex or lower, It depends on the desired application. For non-woven applications, typical deniers are 1.5 to 1.8 dtex, while lower deniers such as 1.2 to 1.5 dtex are suitable for textile applications. The invention also includes fibers having lower deniers as well as fibers having significantly higher deniers, such as 10 dtex or lower, such as 9 dtex or lower, or even 7 dtex or lower. The appropriateness of the fiber fineness is limited to values of 0.5 dtex or higher in many forms, such as 0.8 dtex or higher, and 1,3 dtex or higher. The upper and lower limits disclosed here can be combined and also include the range in which the results are produced, such as 0.5 to 9 dtex. Surprisingly, the discoveries made in this world in the near future will be able to produce fibers with multiple deniers, which can be used in the entire range of fiber applications, including textile and non-woven applications.

If multiple parameters are cited in this case, these parameters are determined as described herein. Basically, these parameters are obtained by fibers like this, and contain a maximum of 1% by weight of additives, such as matting agents, and the fiber is not affected by the process. However, the fibers described herein may of course contain normal amounts of conventional additives, provided that this does not harm the manufacturing of the spinning solution and / or the manufacturing process of the fiber.
The following examples illustrate various aspects of the invention.

method

Measurement of crystallinity index [%] The crystallinity index was measured by Raman spectroscopy. This method was calibrated with data from the X-ray wide-angle method (WAX) and published by Röder et al. (2009) (Röder T, Moosbauer J, Kliba G, Schlader S, Zuckerstätter G, and Sixta H (2009): Comparative Characterisation of Man-Made Regenerated Cellulose Fibers. Lenzing Reports, vol. 87, p. 98).

Determination of water retention capacity [%]
Allow the sample to swell overnight at 20 ± 0.1 ° C. After further dilution, the samples were centrifuged according to Zellcheming Leaflet IV / 33/57 under 3000 times gravity acceleration. This water retention capacity is then calculated as follows:

WRV = (weight of wet sample-weight of dry sample) / weight of dry sample x 100

Examples

Example of setting xylan - mannan ratio <br/> Table 1 shows an example of adjusting the C5 / C6 ratio for two wood species using an example of the H factor when changing the magnesium bisulfite digestion.

Table 1: H-factor adjustment of xylan-mannan ratio in European beech and European spruce magnesium bisulfite cooking.

Example of Eucalyptus Fuel Pulp <br/> In a pilot plant, a new cowhide chemical wood pulp was made from eucalyptus wood using the VisCBC process according to the present invention. The H factor is 1200 and the effective alkalinity in the cooking liquor is 25 g / l. After the TCF process, bleaching is performed. The relevant process data and product attributes are listed in Table 2.

Table 2: Properties from wood to wood pulp to reduced cellulose fiber fibers.

In this new chemical wood pulp with reduced cellulose content, the ratio of the xylan to mannan in the fiber finished product has been extremely increased to 121, and the cellulose content has been kept very low at about 85%. This new wood pulp fully meets the needs of the Lycra fiber process for making new Lycra fibers with reduced cellulose content.

Real fiber properties when using new cellulose-reducing wood pulp Shi example
Table 3 summarizes the sugar monomer content of the starting wood pulp used to make the fiber.


Table 3: Sugar content of cellulose pulp reduced cellulose compared to standard fiberglass pulp

Table 4 shows the mechanical properties of standard fibers (right fibers and rayon fibers) compared to the properties achieved by the right fibers made from the wood pulp of the present invention. The results impressively demonstrate the advantages of the invention.
In pilot plant tests and the large-scale manufacture of nylon fibers according to the present invention, it has been shown that despite the relatively low cellulose content, acceptable strength and workability values can be achieved in terms of commercially relevant fineness. At the same time, the WRV has risen sharply, so this fiber becomes meaningful for the new application areas previously occupied by rayon fibers. However, significantly higher mechanical properties can be achieved with the nylon fiber of the present invention than the commercially available rayon fiber.
Therefore, this new fiber of the present invention combines the advantageous properties of previously commercially available fiber and rayon fibers.


Table 4: Properties of conventional and reduced cellulose lycra fibers compared to standard rayon fibers.

FIG. 1 shows the correlation between the crystallinity and water retention capacity of the fiber and standard fiber of the present invention.

Figure 2 shows the ratio of xylan to mannan in sulfite wood pulp as a function of the H factor when using beech wood.

Figure 3 shows the ratio of xylan to mannan in sulphite wood pulp as a function of H factor when using spruce wood.

Claims (19)

A wood pulp suitable for manufacturing a fiber-formed body, which has a cellulose content of 90% by weight or less, and a hemicellulose content of at least 7% by weight, the wood pulp is characterized in that it is stored in the hemicellulose The ratio of the C5 / xylan to C6 / mannan moiety (C5 / C6 ratio) is in the range of 125: 1 to 1: 3. For example, the cellulose in the first item of the patent application scope, wherein the C5 / C6 ratio is in the range of 25: 1 to 1: 2. For example, for the wood pulp in the scope of claims 1 and / or 2, the proportion of the hemicellulose is 10% by weight or more. As for the wood pulp of at least one of the above-mentioned patent applications, the hemicellulose exists in a natural state and has been chemically modified through a processing process, or has been chemically modified or functionalized in a separate process step. The wood pulp according to at least one of the above patent applications has a lignin content of more than 1% by weight. The wood pulp according to at least one of the above patent applications, wherein the cellulose content is further reduced by the presence of lignin, ancillary components and / or metal compounds from the wood. The wood pulp according to at least one of the aforementioned patent applications has a xylan content of 9% by weight or more and / or a mannan content of 6% by weight or more. For example, the wood pulp of item 7 of the patent application scope has a xylan content of 9% by weight or more and a mannan content of 1% by weight or less. A lyophilized fiber formed body is prepared by using wood pulp as described in any one of claims 1 to 8 of the patent application scope. For example, the fiber-formed body of item 9 of the patent application scope, wherein the forming system is selected from the group consisting of fibers, filaments, staple fibers, nonwoven knits, films, and spherical powders. For example, the fiber-formed product of at least one of the items 9 and / or 10 of the scope of the patent application, wherein the forming system fiber, filament or staple fiber has a cellulose content of less than 90% by weight and a content of more than 5% by weight And a C5 / C6 ratio of 125: 1 to 1: 3, preferably 25: 1 to 1: 2. For example, the fiber-formed body of at least one of items 9 to 11 of the patent application scope, wherein the hemicellulose content is higher than 10% by weight. For example, a fiber-formed body of at least one of the items 9 to 12 of the scope of application for a patent, wherein the forming system has a fiber and filament of WRV higher than 70%, preferably higher than 75%, especially higher than 80% Or short fibers. For example, a fiber formed article of at least one of items 9 to 13 of the patent application scope, wherein the formed article has a crystallinity of 40% or less. For example, the fiber-formed body of at least one of the items 9 to 14 of the patent application scope has a lignin content higher than 0% to 5% by weight. A method for manufacturing a lyophilized fiber formed body comprising dissolving a wood pulp having a cellulose content of 90% by weight or less and a hemicellulose content of at least 7% by weight in a suitable solvent, and forming the solution into a lyophilized product. The fibrous formed body is characterized in that the ratio of C5 / xylan to C6 / mannan (C5 / C6 ratio) existing in the hemicellulose is in the range of 125: 1 to 1: 3. For example, the method of claim 16 in the patent application scope, wherein the fiber-forming system is obtained through a fiber spinning process. A method for manufacturing wood pulp according to any one of claims 1 to 8 of the scope of patent application, the method comprising at least one of the following steps: a) mixing pure wood pulp with xylan and / or mannan; b) chemically and / or physically treating wood pulp having a hemicellulose content including mannan to change the hemicellulose content and / or hemicellulose composition contained therein; c) Use of coniferous and / or deciduous wood to make wood pulp; d) mixing wood pulp without mannan with hemicellulose-rich wood pulp, and optionally chemically and / or physically treating the mixture thereafter to adjust the hemicellulose content and / or The composition of the hemicellulose part; e) mixing two wood pulps having different hemicellulose content and / or hemicellulose composition, and thereafter chemically and / or physically treating the mixture as necessary to adjust the hemicellulose content and / or the hemicellulose Composition of cellulose part. For example, the method of claim 18 of the patent scope, wherein the different wood pulps are selected from wood pulps based on hardwood and softwood.