Compression hosiery

Abstract

FIELD: textile industry.SUBSTANCE: invention relates in particular to the production of medical and sports compression knitwear using a flat knitting method. The compression knitted product is made in the form of a three-dimensional seamless tubular structure on a flat knitting machine, wherein said structure has a continuous integral structure along the entire length of the product with compression pressure distribution along the length of the product, wherein the distribution of compression pressure changes smoothly from the distal part to the proximal part of the product with a decrease in the direction towards the proximal part, and the connection lines formed during the knitting process have an extensibility and structure identical to the extensibility and structure of the main fabric.EFFECT: ensures the absence of structurally pronounced connection zones, increased wearing comfort, improved uniformity and accuracy of compression pressure distribution over the entire surface of the limb, elimination of potential points of skin irritation, as well as increased strength of the finished product.1 cl, 7 ex

Description

[0001] The invention relates to the textile industry, specifically to the production of medical and sports compression hosiery using a flat knitting method. The hosiery is designed to create measured, graduated, or distributed pressure on human limbs and can be used as medical devices (for the treatment and prevention of chronic venous diseases and lymphostasis), sports equipment, and rehabilitation products.

[0002] Further in the text, the applicant provides explanations that are necessary for a clear understanding of the essence of the declared materials and the elimination of contradictions and / or controversial interpretations when performing an examination on the merits.

[0003] Compression hosiery for medical and sports use is traditionally manufactured in two main ways, each of which has fundamental technological and consumer limitations.

[0004] The most common production method is knitting on cylindrical circular knitting machines. This technology creates seamless (tubular) fabric by continuously moving needles in a circle. Products such as stockings, socks, or knee-highs are formed as finished tubes of a given diameter, eliminating the need for subsequent longitudinal seaming. However, despite the apparent perfection of seamless construction, circular knitting has significant drawbacks when applied to highly functional compression knitwear. The main limitation is the lack of flexibility in creating complex fabric structures and precise anatomical shaping. The machine operates with a fixed number of needles per pattern, which hinders localized variations in knitting density, the creation of complex weaves for compression zones, and the seamless integration of anatomical elements (such as a heel cup or reinforced arch support).As a result, the creation of truly graduated pressure (a gradual decrease in compression from the ankle to the calf) is often achieved only through the selection of elastic threads, and not through the programmable geometry of the fabric itself, which reduces the accuracy and reproducibility of the therapeutic effect.

[0005] To overcome these design limitations in the production of medical hosiery, for example, high-compression garments, flat knitting technology is used on flat knitting machines. This method provides the highest level of process control. The programmable movement of each needle allows for the creation of complex fabric shapes with variable density in each row and stitch, integrating sections with different elasticity and structure, ensuring precise compliance with medical pressure gradient requirements. However, a key technological drawback of this method is that the product is produced as an unfolded flat sheet. To give it the required tubular shape (for example, for a stocking), two separate knitted fabrics are sewn together along a line, forming a longitudinal connecting seam.This seam becomes a weak point in the finished product: it can cause discomfort and chafing, especially in patients with increased sensitivity; it acts as a localized compression "rib," disrupting the uniformity of pressure distribution; it is a potential area of ​​mechanical stress and rupture, reducing the durability of the product; and it also detracts from its aesthetic appearance.

[0006] Therefore, there is a clear technological gap in the current state of technology: circular knitting produces seamless, but structurally simple and insufficiently precise products, while flat knitting provides high functionality and precision, but inevitably leads to the formation of problematic connecting seams. Therefore, the development of a compression knitwear product that combines the advantages of flat knitting technology (programmability, complex structure, precise pressure gradient) with the consumer benefits of seamless circular knits (comfort, pressure uniformity, increased strength) is a pressing technical challenge, which is addressed by the proposed technical solution.

[0007] From the prior art research, the applicant has identified a utility model under Russian Patent No. 211569, "Lower Body Garment." The invention is a lower body garment comprising a waistband, trousers sewn to the waistband and compression elements, and compression elements. The garment is characterized by being form-fitting, the compression elements are U-shaped, and encompass the lateral and upper surfaces of the calf muscles. The compression elements are made of a less stretchable material than the remaining portions of the trousers.

[0008] A drawback of the known technical solution, which involves sewing individual U-shaped compression elements into the leg structure, is the fundamental impossibility of ensuring uniform, continuous, and physiologically correct distribution of compression pressure across the entire surface of the limb. Since the compression elements are separate components sewn to the main fabric, the product inevitably has numerous connecting seams. These seams create localized points of increased mechanical pressure and friction, leading to discomfort during wear, the risk of irritation of sensitive skin, and are a structural weakness that reduces the overall strength and durability of the product.

[0009] In addition, the production of such a product is multi-stage and less efficient, requiring separate operations for cutting and sewing parts, which increases labor intensity and does not allow for precise programming of compression properties during the production process.

[0010] The technical result of the claimed invention is the creation of a compression knitted garment manufactured on flat knitting machines and without a connecting longitudinal seam, which ensures increased wearing comfort, improved uniformity and precision of compression pressure distribution over the entire surface of the limb, the elimination of potential points of skin irritation, and increased strength of the finished product.

[0011] The stated technical result is achieved The fact that the claimed compression knitted product is manufactured on flat knitting machines, preferably of the double-bed type with electronic control, which allows the formation of the finished tubular structure of the product directly during the knitting process without longitudinal stitching.

[0012] A distinctive feature of the invention is the use of a closed-loop cyclic knitting method. Unlike traditional flat knitting, where the fabric is formed unfolded, in the claimed solution, the front and back sections of the garment are knitted sequentially on the first and second needle beds of the machine. The transition between needle beds is accomplished not by forming an open edge, but by forming a connection along the side lines. This connection is achieved by closing and knitting specially formed edge loops together, resulting in a single tubular piece. Thus, the side lines are not a seam, but a technologically integrated connection zone, the elasticity and structure of which are identical to the main fabric, eliminating the formation of a hard scar.

[0013] Precise control of compression properties, as well as the creation of a specified pressure gradient, is ensured by complex programming of knitting parameters, which is transmitted to the control program for the knitting machine via several independent channels:

[0014] • Gradient knitting density regulation, in which the number of loops per unit length changes smoothly along the length of the product (for example, maximum density in the ankle area with a gradual decrease towards the knee), which is the main mechanism for creating graduated compression.

[0015] • Differentiated thread feed and tension: A composite system is used, consisting of a low-stretch textured thread (polyamide, polyester, polyester) and a highly elastic thread (lycra, elastane, spandex). The feed and pre-tension of the elastic thread can be programmably varied in different areas of the fabric, providing localized compression correction and an anatomical fit.

[0016] • Within a single product, various types of weaves can be combined (satin, elastic, press weave, openwork, derivatives, jacquard), which allows you to create zones with different degrees of stretchability, rigidity and breathability without compromising the integrity of the fabric.

[0017] The formation of complex anatomical zones (heel, toe, kneecap) is achieved through partial knitting and stitch transfer techniques integrated into the overall tube creation cycle. This allows for the seamless incorporation of volumetric elements, pockets, and reinforcement zones that precisely follow the contours of the body.

[0018] The increased product strength is a direct result of eliminating the connecting seam, a traditional stress concentration point. The seamless monolithic structure distributes the load more evenly, increasing tensile strength and extending service life.

[0019] The pressure gradient is created by varying the knitting density (the number of loops per unit length) along the length of the garment during its production, for example, with a minimum density in the proximal portion and a maximum density in the distal portion. This ensures anatomically correct compression distribution, with maximum, up to 100%, compression in the distal portion. These garments are also available with compression values ​​ranging from 5 to 45 mmHg.

[0020] Thus, a combination of three factors - 1) seamless tubular knitting technology on a flat knitting machine, preferably a double-bed type; 2) programming the parameters of the material and structure of the fabric; and 3) integrating shape-forming elements into the knitting process - allows us to achieve the stated technical result: to obtain a compression knitted product made on flat knitting machines and without a connecting longitudinal seam.

[0021] The essence of the declared technical solutionA tubular compression knit garment that can be made into tights, stockings, knee-highs, socks, sleeves, gloves, or face masks is produced on a flat knitting machine, preferably a double-bed machine, using cyclic cross-loop knitting along a closed loop. The tubular structure is formed not by subsequent seaming, but directly during the knitting process through the coordinated interaction of both beds, sequentially knitting the front and back of the garment and connecting them with edge loops along the side lines.

[0022] The applicant then provides a description of the claimed technical solution.

[0023] The claimed invention is a one-piece, longitudinally seamless compression knitted garment, the main tubular portion of which has no cuts or seams running along the limb.

[0024] This product is characterized by a monolithic tubular structure, which lacks the traditional connecting seam typical of classic flat-knitted garments. The side seams of the garment are not stitching lines, but rather technological joining lines formed directly during the knitting process by the interweaving and closing of loops knitted on opposite needle beds. These lines have physical and mechanical properties (elasticity, thickness, surface density, and structure) identical to the main fabric, making them visually and tactilely indistinguishable and completely eliminating the discomfort associated with the friction of a rigid seam against the skin. The design of the garment may include complex anatomical elements, such as the heel, toe, instep, kneecap, or elbow area, which are integrated into the overall seamless tubular structure using a form-forming knitting method rather than by sewing individual parts on.

[0025] To ensure the specified compression, performance, and hygienic properties, a combined system of yarns fed into the knitting zone is preferably used. The system includes at least two main components, such as:

[0026] A highly stretchable interlining thread designed to form a stable, strong, and wear-resistant fabric frame. This thread is preferably a textured synthetic mono- or multifilament thread based on polyamide (e.g., nylon-6, nylon-6,6) or polyester (polyethylene terephthalate) with a linear density ranging from 44 to 100 dtex. This thread ensures the product's shape retention, durability, and resistance to mechanical stress.

[0027] A knitting thread, which is the functional component providing the primary compressive effect. Preferably, elastane-based threads (Lycra, Dorlostan, etc.) are used, either bare or as part of a braided or wrapped thread, with a linear density of 20 to 270 dtex. This thread is characterized by a high modulus of elasticity and the ability to withstand significant reversible deformation. The key technological parameter controlling the final compressive force is the pre-tension of this thread as it is fed into the loop formation zone, which can be varied programmatically depending on the knitting section.

[0028] Additional functional threads that can be locally introduced into the fabric structure to impart special properties. These threads include: hygroscopic threads (cotton, viscose, bamboo) introduced into areas of increased sweating; threads with antimicrobial impregnation or containing silver ions; thermosetting threads for creating zones of rigid stabilization; reflective or hydrophobic threads.

[0029] The garment is produced on a flat knitting machine, preferably a double-bed machine (e.g., with a V-shaped needle bed or parallel needle beds), equipped with a computer control system. Importantly, it has independent and programmable control of each needle or group of needles on both beds (front and back). This technique, known as "tubular knitting on a flat machine" or "circular knitting on a double-bed flat machine," involves sequentially knitting rows of stitches on opposite beds while simultaneously joining the edges.

[0030] The applicant further provides the principle of manufacturing the claimed compression knitted product on a flat knitting machine. .

[0031] The production process of the declared product is based on the use of specialized software for product design and computer control of a double-bed flat knitting machine.

[0032] Development begins with the creation of a digital model that takes into account the limb's geometry. Based on this model, a control program for the knitting machine is generated.

[0033] The essence of the claimed technical solution lies in the formation of a tubular structure directly during the knitting process through the coordinated interaction of both needle beds of the machine. The garment is created cyclically, without removing the fabric from the needles, by alternately knitting sections corresponding to the front and back of the garment and seamlessly joining them along the side lines in each cycle. The joining is achieved technologically through the interweaving of the threads, eliminating the formation of a traditional longitudinal seam.

[0034] To achieve a specified pressure gradient, the program synchronizes key parameters in real time: knitting density, elastic tension, and fabric structure. This allows for the creation of a seamless, one-piece garment with precisely programmed compression properties.

[0035] To seamlessly form three-dimensional elements (heel, toe, glove thumb) at specified points, the program switches the machine to partial (figured) knitting mode. In this mode, not all the needles are used, but only a subset. For example, to create the heel of a sock, the outer needles are sequentially removed, and the section is knitted only with the central needles, creating a three-dimensional pocket. After the element is formed, the system returns to the basic cyclic knitting algorithm for a tube.

[0036] Smoothly changes the knitting density (the number of stitches per unit length). The density gradually decreases from the distal (farthest) part of the limb to the proximal (nearest) part, for example, from the ankle to the knee, creating a basic therapeutic pressure gradient.

[0037] In areas requiring maximum compression, the elastane feed servo increases tension, delivering a more compressed, energy-rich yarn to the knitting area. As the yarn moves upward, the tension decreases.

[0038] Different sections of the fabric can be made with different types of knitting stitches (stockinette, rib knit, their derivatives, and simple jacquard weaves), which have varying degrees of stretch, stiffness, and rebound strength. Stiffer stitches are placed in areas requiring maximum support, while more elastic stitches are used in areas of comfortable fit.

[0039] Thus, the peculiarity of the claimed invention is the integrated approach, consisting of a specially selected system of materials, adapted technological equipment and complex software control, which together makes it possible to obtain a compression product devoid of the fundamental disadvantages inherent in both circular and classic flat-knitted analogues.

[0040] Below are examples of the implementation of the declared technical solution.

[0041] The invention can be implemented in a wide range of compression knitwear manufactured using the claimed seamless tubular knitting technology on a double-bed flat knitting machine. Specific implementation examples are provided below.

[0042] Example 1. Compression sock.

[0043] A three-component yarn delivery system is used to form the fabric. The frame and outer wear-resistant surface are formed from, for example, a textured polyester polyfilament yarn with a linear density of, say, 78 dtex. Compression force is created by, for example, a highly elastic polyurethane yarn (Lycra) with a density of, say, 156 dtex, delivered with variable, programmable tension. In areas of increased heat generation (sole, instep), a hygroscopic and antimicrobial yarn is integrated, for example, based on polyamide with a microfiber structure and the addition of silver ions.

[0044] The knitting process begins with a seamless cuff knitted in 1x1 rib stitch. The machine then switches to cycle knitting to form the shaft. The density gradient is programmed so that the maximum number of stitches per inch is achieved at the ankle, gradually decreasing (by approximately 8-10%) towards the top of the shaft by reducing the number of needles inserted in each subsequent cycle. At the heel, a complex partial knitting algorithm is activated: first, the outer needles on the front and back beds are successively removed from work, and only the central group (approximately 60% of the total) is knitted, forming a cup-shaped pocket. After knitting the set pocket depth, the needles are gradually reinserted to create the instep. The toe is formed in a similar, but mirrored, manner.In the arch area, the knitting density is locally increased by 15% by adjusting the needle pitch and increasing the Lycra tension, creating a supportive arch effect. All technological transitions are performed without thread breakage, resulting in a seamless product without a single longitudinal or rough transverse seam.

[0045] Example 2. Medical compression stockings, compression class II (23-32 mmHg).

[0046] Uses a smooth polyamide thread with a linear density of 44 dtex, ensuring minimal friction and high tensile strength. The elastic reinforcement component is a thin rubber cord (latex or synthetic rubber) with a diameter equivalent to 210 dtex, braided with a polyester sheath for protection. The tension tolerance of this thread should not exceed ±2%.

[0047] The process begins with knitting the main tubular section. The control program synchronizes three independent loops: 1) Density loop: the needle pitch gradually increases, decreasing the density by 12% from point B1 to the top edge along a preset nonlinear curve. 2) Elastic thread tension loop: the feed servo loosens the thread tension by 30% along the same gradient. 3) Weave loop: the lower third of the garment uses a reinforced weave for minimal stretch, gradually changing to a standard rib knit at the top for a better fit.

[0048] At the ankle (minimum circumference), the knitting density and elastane tension are at their highest. As you move toward the calf, the density gradually decreases (by 5-10% every 2 cm), and the elastic thread tension is relaxed, providing pressure relief.

[0049] The heel area uses a partial knitting technique. The machine, continuing the tubular format, knits stitches only on a portion of the needles of both foundations, creating a voluminous pocket that precisely follows the anatomy. After knitting the pocket, work returns to the cyclical knitting of the main tube of the shin.

[0050] The garment comes off the machine as a finished tubular piece without a longitudinal seam. It only requires closing the open edge (sock) or joining it to other parts (foot and shin in socks) on a chainstitch sewing machine (a more elastic seam) or on the same knitting machine.

[0051] The resulting product has no longitudinal connecting seam, has perfectly graduated pressure set by the program, and is highly comfortable to wear.

[0052] Example 3. Compression stocking of class I compression (18-22 mmHg).

[0053] The lining thread used is a matte 160 dtex polyamide thread. For the inner layer in contact with the skin, a soft ring-spun combed cotton thread is used throughout the foot and lower leg. Compression is provided by a binder thread, such as 70 dtex elastane in a polyamide braid, preventing direct contact of the latex with the skin.

[0054] The manufacturing process involves creating a seamless tubular fabric from the toe to the upper third of the thigh with a seamless heel and anatomical widening at the knee. The heel is created using an intensified partial knitting method with a deep pocket. The widening from the ankle to the calf and further to the thigh is achieved not by knitting a separate piece, but by programmatically adding stitches. At certain knitting cycles, at precisely calculated moments, additional needles from the reserve are added to both needle beds. This results in a smooth increase in the tube's diameter. All joining lines, including the transition to the added stitches, are technologically seamless. The upper edge can have an integrated silicone strip or an openwork flanging for fixation.

[0055] Example 4. Compression tights

[0056] A complex of three main threads: a durable polyamide thread for the frame, a low-density polyfilament Lycra for uniform compression, and natural cotton or modal for insertion in the groin area and upper abdomen for increased hygroscopicity.

[0057] First, the first seamless tubular leg is knitted (from the cuff to the top of the thigh) using the described cyclic method. Then, without removing the fabric, the machine switches to knitting the second symmetrical leg using a stitch transfer.

[0058] After completing the second leg, the machine switches to flat (non-tubular) knitting for the wide panel that will form the crotch, waistband, and front belly. At this point, a cotton insert is integrated into the crotch area. The panel is knit so that its side edges are joined (by closing the stitches) to the edges of both legs. This creates a seamless panel-leg connection.

[0059] A waistband is formed with elastic or a wide silicone band. The finished product is one-piece, with all critical joints for comfort being knitted rather than seamed.

[0060] Example 5. Compression sleeve

[0061] Functional synthetic threads are used, such as polyester with a wicking effect for rapid moisture wicking, as well as highly elastic Lycra for precise compression. In the elbow or forearm area, a highly stretchable thread (such as Lycra or spandex) or silicone rubber thread can be woven in to create a stabilizing mesh.

[0062] The sleeve is knitted as an anatomically curved tube for a better fit. The curve is achieved by asymmetrically programming the row lengths on the inner and outer sides of the tube. A combined method is used for the elbow area: first, a reinforced "cup" is created using partial knitting, then a special weave (such as "cross rib") is used in this area, and a stabilizing thread is introduced. The top and bottom edges feature integrated silicone printing: on the final knitting rows, a silicone monofilament is inserted into the fabric structure. When heat-set after removal from the machine, this creates non-slip dots that are invisible from the front.

[0063] Example 6. Compression mask

[0064] We use the finest biocompatible threads, such as polyamide-based microfiber with a density of, say, 20 dtex, and ultra-fine polyurethane thread with a density of, say, 30 dtex for light compression for softness. All materials undergo hypoallergenic treatment.

[0065] This process represents the pinnacle of 3D knitting complexity. A 3D scan of the face is used to create a digital model, which is then converted into a program using hundreds of partial knitting zones. The nose protrusion is formed by repeatedly knitting short rows on a very limited number of needles, creating volume. The eye holes, conversely, are formed by skipping rows and creating openwork sections. The mouth can be left open or a stretchable mesh insert can be knitted. The entire mask is knitted as a single piece, with smooth transitions between the volumetric zones and flat areas. The edges of the mask are finished with a border of the same yarn as the main fabric to prevent curling.

[0066] Example 7. Compression gloves

[0067] The knitting process begins with the formation of the fingers, followed by the palm and seamless cuff. Each finger (starting with the thumb) is knitted as a separate miniature tube on a dedicated group of needles. The same cyclic technique is used, but on a micro-scale. After completing a finger, its open loops are temporarily transferred to an auxiliary holding needle bed or secured, and the yarn is broken. The needles are then released for knitting the next finger. After all the fingers are knitted, their open loops are joined to the main palm by closing rows, creating a seamless "finger-palm" transition. The thumb area is shaped similarly, but with a separate corner entry. The palm can be reinforced with interwoven silicone thread.

[0068] Thus, from the above, it can be concluded that the stated technical result has been achieved, namely, a compression knitted product has been created, manufactured on a flat knitting machine and without a connecting longitudinal seam, which provides increased wearing comfort, improved uniformity and accuracy of compression pressure distribution over the entire surface of the limb, elimination of potential points of skin irritation, as well as increased strength of the finished product.

[0069] The claimed technical solution meets the “novelty” criterion imposed on utility models, since, when determining the level of technology, no technical solution was identified that has features identical (that is, coinciding in the function they perform and the form of execution of these features) to the set of features listed in the formula of the utility model, including the characteristic of the purpose.

[0070] The claimed technical solution meets the “inventive step” criterion required for inventions, since no technical solutions have been identified that have features that coincide with the distinctive features of the claimed invention, and the influence of the distinctive features on the specified technical result has not been established.

[0071] The declared technical solution meets the “industrial applicability” criterion imposed on utility models, since it can be manufactured using known materials, components, standard technical devices and equipment.

Claims

A compression knitted product made in the form of a three-dimensional seamless tubular structure on a flat knitting machine, characterized in that said structure has a continuous, integral structure along the entire length of the product with a compression pressure distribution along the length of the product, wherein the distribution of the compression pressure changes smoothly from the distal part to the proximal part of the product with a decrease in the direction towards the proximal part, and the connection lines formed during the knitting process have an extensibility and structure identical to the extensibility and structure of the main fabric, which ensures the absence of structurally distinct connection zones.