JP2014503703A - Method for producing milk protein fiber and milk protein fiber product obtained from the method - Google Patents

Abstract

Milk protein fiber is produced, inter alia, by an extrusion process for the textile industry, and at least one thermoplastic protein obtained from milk is at room temperature to 140 ° C. under mechanical stress with a plasticizer such as water or glycerol. It is plasticized and spun into fibers by a nozzle.
[Selection] Figure 1

Description

  The invention relates in particular to a process for producing milk protein fibers for the textile industry and hygiene and medical products, as well as raw cotton, wool, loose staple fibers, yarns, textiles and knitted fabrics produced by the fibers according to the invention And related milk protein fiber products such as other products.

Milk protein fibers belong in a broad sense to protein fibers which also include the natural products wool and silk. Protein fibers have long been known on a technical scale. Casein fiber was already produced in the 30s. Casein is a protein fraction derived from mammalian milk. Casein is produced from skim milk that is coagulated at 45 ° C. by an acid near pH 4.6 (the isoelectric point of casein). Alternatively, a lab is used for solidification. The solid is separated or extruded and washed several times. Finally, drying at 50-80 ° C. is carried out, resulting in a residual water content of less than 10% (Rompp Chemielexicon, Georg-Thieme-Verlag, 1989 ⁹ under “casein”). Casein is a mixture of several proteins, the most important of which are generally designated αS1, αS2, β and κ (milk). White to yellowish slightly hygroscopic casein powder is insoluble in water but soluble in alkali, so it works in an alkaline environment and solution spinning process where the fiber is subjected to other processing steps and later baths Requires a classic manufacturing method. The protein is dissolved in alkali, filtered, cleaned, extruded with a nozzle into an acid bath, sucked, and hardened with formaldehyde or aluminum sulfate (see Rompp above).

  In a classic wet spinning process, the aqueous casein solution is coagulated with sodium carbonate at a pH value of 7-10, stirred for 24 hours at room temperature and degassed in vacuo before further processing. The solution is then extruded into a coagulation bath containing aluminum sulfate 18 hydrate, sodium chloride and sulfite. The milk fiber is then cured for 24 hours in a curing bath with sodium acetate trihydrate and a formalin solution with a pH value of 5.5. The fibers are then removed from the curing bath residue under running water for 24 hours and dried at room temperature. The contamination level and water consumption caused by the coagulation bath are very high. Furthermore, this method requires a lot of time and the processing time is about 60 hours.

  From Patent Document 1, for example, a curing bath corresponding to the above is known.

  U.S. Patent No. 6,057,032 describes a method for preparing a material containing casein. Thus, a plastic mass produced from water and protein is extruded into a gas atmosphere by an extruder. In this method, extrusion is performed at a temperature of 100 ° C., whereas it is important that the material must be heated within the post-treatment range.

  This requires long production times and additional energy.

  For the above method, the final product is used in the field of food. For this reason, proteins are disclosed exclusively as classifiers. That is to say in particular the origin of gelatin and fish and meat. The product thus obtained is water-soluble and does not have sufficient tensile strength.

German Patent No. 905418 European Patent No. 0051423 A2

  The object of the present invention is to avoid the above disadvantages and shorten the machining time. At the same time, water and energy consumption is reduced.

  This problem is solved by the method according to claim 1. Here, at least one protein obtained from milk is plasticized with a plasticizer under mechanical stress at temperatures ranging from room temperature to 140 ° C. and spun into fibers via a nozzle. Here, the plasticizer is selected from the group consisting of an aqueous polysaccharide solution, an alcohol, a polyhydric alcohol, or a mixture of these substances.

  According to the invention, it is proposed to use alcohols or polysaccharides as plasticizers. Due to the use of these newly proposed plasticizers, it is possible to produce milk protein fibers that do not contain the disadvantages of the prior art.

  The present invention is based on the finding that milk proteins and especially casein can be plasticized in the heat by kneading and thereby processed in melt spinning. In melt spinning, the dried dissolvable raw material is plasticized by heat and is extruded as a melt through a nozzle, preferably by a gear pump or an extruder. After extrusion, the melt solidifies. The drawn yarn is wound up or further processed if desired. The drawn yarn may be sucked before being wound or may be surface treated.

  To achieve even milder processing, the protein is mixed or kneaded with the plasticizer and at the same time subjected to mechanical stress.

  The milk protein is preferably casein or lactalbumin.

  Proteins obtained from milk can be produced in situ by precipitation from milk. According to the first procedure, milk in the form of a rub, a mixture with other suitable enzymes or acids can be immediately introduced into the processing as an agglomerated mixture or the extruded agglomerated protein is used in wet form. May be. According to another optional procedure, the pre-separated and prepared, if necessary, pure or mixed protein, i.e. the protein fraction from milk, may be used, for example in the form of a dry powder. Good.

  The milk protein used according to the invention can be mixed with other proteins in a proportion of not more than 30% by weight with respect to the milk protein. For this, other albumins such as ovalbumin and vegetable proteins, in particular lupine protein, soy protein or wheat protein, in particular gelatin may be used.

  The plasticizer is preferably water used in a proportion comprising 20-80% with respect to the weight of the protein, preferably in a proportion comprising about 40-50% by weight of the protein content. Other plasticizers, in particular alcohols, polyhydric alcohols, gum arabic, aqueous sugar solutions, and in particular aqueous polysaccharide solutions may be used instead of water or those mixed therewith. If necessary, the water content of the protein fraction must be taken into account.

  In particular, the following plasticizers and related proportions are particularly preferred:

  Alcohols and polyhydric alcohols are used in a proportion of about 10% by weight or less with respect to proteins, with glycerol (glycerin) being particularly preferred. Other polyols such as ethylene glycol may alternatively be used. Carbohydrates and polysaccharides are each used in a ratio of preferably 0.4 to 2% by mass in a 70% aqueous solution. Starches of different origin such as carrageenan, cellulose, especially carboxycellulose and chitosan are preferred.

  The addition of other agents is not excluded. Additives and auxiliaries such as lipophilic additives, polishes and crosslinkers may be specifically provided. Both additives and auxiliaries do not exceed a maximum of about 30% by weight of protein. Vegetable oils may be selected as lipophilic additives that slightly hydrophobize the existing fiber during the plasticizing operation. In addition, waxes that additionally provide fiber stability may be used. Preferred waxes are carnauba wax, beeswax, candelilla wax and other naturally obtained waxes.

  Calcium salts such as calcium chloride, dialdehyde starch and glucose-δ-lactone are preferred as crosslinkers.

  In a highly preferred embodiment, plasticization is performed by an extruder and all selected materials are premixed and then fed into the extruder or only a portion of the material or only the protein is filled at the start. And other materials are added at the feed spot along the extrusion process, ie along the screw.

  In a highly preferred embodiment, the protein is fed to the extruder as a dry powder via a hopper at the inlet of the extruder, whereas plasticizer and especially water is added into the plasticizing zone in a subsequent extrusion step. Be provided. Furthermore, it is preferred that all dry starting materials are premixed and fed into the extruder at the start, whereas all liquid components are mixed downstream. At the exit of the extruder, the extruded material is extruded through a nozzle, thereby forming fibers.

  Where proteins are used as agglomerated raw material mixture, procedures are preferred in which dehydration can be performed along an extruder or other processing equipment.

  Due to plasticization, the operation corresponds to melt extrusion. In this thermoplastic extrusion, the material is transformed into a plastic state via heating and thus deforms. Here, the temperature exceeds the gas transition temperature of the protein, and this material changes from an amorphous to a rubbery plastic state. If the compaction and kneading is very strong, heat does not need to be supplied from the outside since it can happen that heat is already generated by mechanical stress. Extrusion then takes place already at room temperature. However, usually very specific temperatures that allow optimal plasticization must be set in different extruder zones. Preferably, the material is extruded in an extruder at 30-95 ° C, more preferably 50-90 ° C, most preferably about 60-80 ° C.

  Furthermore, the formed fibers are preferably wound after exiting the nozzle and dried before and / or after this step.

  After the formed fibers exit the nozzle, the fibers may be cut immediately, eg, cut into short fibers, or further processed into staple fibers.

  Immediately after the formed fiber exits the nozzle or in at least one subsequent processing step, the fiber may alternatively be further processed into a combined yarn, in particular it may be knitted into raw cotton, loosely wound up, or fleece It may be further processed.

  In the importance of the present invention, the fiber may pass further through the bath before being wound up, but this procedure is less preferred and is not usually required. Alternatively, the fibers may be subjected to a spray treatment after exiting the nozzle. Here, smoothing agents, waxes, lipophilic agents or cross-linking agents may be applied to the surface of the fibers, for example. In the case of cross-linking agents, the cross-linking agents described above, ie generally different salt solutions, preferably calcium chloride solutions, dialdehyde starch solutions, glucose-δ-lactone solutions or aqueous lactic acid solutions are preferred.

  The resulting fibers can be used for all possible purposes. They can be used like common textile fibers and can therefore be processed into all kinds of textiles such as textiles, woven fabrics, knitted fabrics, crocheted knitted fabrics, yarns, ropes, fleeces, felts and the like. Raw cotton, loose fiber insulation, filters and membranes may also be obtained from the fibers according to the invention. Thus, the field of application of milk fiber includes, inter alia, medical products such as swabs, filters and membranes due to textile technology, building insulation and building materials, hygiene products and the inherent antibacterial action.

  Accordingly, part of the present invention is also a milk protein fiber product, which contains fibers containing milk protein that is thermo-mechanically plasticized, in particular obtained by the method according to the invention described above.

  If the fibers are loosely wound, it is possible to produce a raw cotton or fleece that can be used, for example, as a filling and filling material.

  It is particularly preferred that the fibers are knitted into yarn. It is now possible to knit several milk protein fibers produced by the method according to the invention together and to knit milk protein fibers in combination with other natural or synthetic fibers. Elastane (spandex), viscose, silk or wool may also be used, for example, as other fibers that can be spun and / or knitted in the mixture to match yarns.

  A single fiber is obtained by a discontinuous procedure. The fibers may also be cut into short fibers or staple fibers.

  On the other hand, the fabric may be produced from the resulting fibers, filaments or yarns. Therefore, all types of woven and knitted fabrics also represent milk protein fiber products according to the invention.

  The advantage obtained by the present invention is that, in particular, during the production of milk protein fibers, the extrusion process allows the removal of substances that are hazardous to the health and harmful to the environment from the process and from the fibers themselves. Based on the fact that In addition, considerable resources of energy, water, time and human resources can be saved, improve environmental protection and increase economic efficiency. Particularly beneficial properties of fibers that are very suitable as textile fibers are based on the structural changes that solidify during plastification (fabric structure). More detailed knowledge about the mechanism has not been obtained so far.

The extrusion process is shown.

  In the following, the invention is described in detail by means of exemplary embodiments. The exemplary embodiments are provided for purposes of illustration only and are not intended to limit the invention. Based on this exemplary embodiment and its technical information, one of ordinary skill in the art can find other possible embodiments by changing the parameters.

  Example 1: Production of milk protein fiber having a strength of 20 dtex. Dr. having a diameter of 30 mm. Extrusion is performed with a Collin single screw extruder Model 30E. Heating is performed in four cylinder heating zones using the following temperature development: 65 ° C, 74 ° C, 75 ° C, 60 ° C.

  Casein powder is fed through a vibrating conveyor. Water is added at a ratio of 1: 2 (water: casein) by a peristaltic pump. Fiber strength is defined by nozzle strength. The fiber can have a strength of, for example, 20 dtex. The fiber is wound up by a winding machine and dried at room temperature.

  The extrusion process is further represented in FIG.

  The extruder 1 is filled with casein powder through a hopper 2. The casein powder is heated in an extruder. Water is added as a plasticizer by a peristaltic pump. The final product is extruded through nozzle 4. The fiber strand is wound up by a suitable winding technique and dried in a winder 5 at room temperature.

Claims (14)

  A method of producing milk protein fibers, wherein at least one protein obtained from milk is plasticized with a plasticizer at room temperature to 140 ° C. under mechanical stress and spun into fibers through a nozzle. The method is characterized in that the plasticizer is selected from the group consisting of aqueous polysaccharide solutions, alcohols, polyhydric alcohols or mixtures of these substances.   The method according to claim 1, characterized in that the protein obtained from milk is produced in situ by precipitation from milk.   The method according to claim 1, characterized in that the protein obtained from milk is used in the form of a protein obtained separately in advance.   The method according to claim 1, wherein the protein obtained from milk is casein.   The method according to any one of claims 1 to 3, wherein the protein obtained from milk is lactalbumin.   6. Process according to any one of the preceding claims, characterized in that the plasticization is carried out at a temperature up to 80 [deg.] C.   Process according to any one of the preceding claims, characterized in that other additives and auxiliaries are added to the starting material to be plasticized.   The plasticization is performed by an extruder, and the fibers are extruded through and formed by a nozzle at the outlet of the extruder. the method of.   The method according to claim 1, wherein the formed fibers are wound up.   10. A method according to any one of the preceding claims, characterized in that the formed fibers are dried.   11. A method according to any one of the preceding claims, characterized in that the formed fibers are cut immediately after leaving the nozzle.   12. A method according to any one of the preceding claims, characterized in that the formed fibers pass through a bathtub before being wound up.   12. A method according to any one of the preceding claims, characterized in that the formed fibers are subjected to a spray treatment before being wound up.   Milk protein fiber product containing fibers produced according to the method of any one of claims 1-13.

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