Method for producing an object having a fluorinated polymer coating

Abstract

SOLUTION: A method of producing an object having a fluorinated polymer coating free of per- and polyfluorinated acids and salts thereof comprises a step DF of depositing a fluorinated polymer coating on the object by means of plasma polymerization of a fluorinated precursor monomer and a step IG of exposing the object to an inhibiting gas which inhibits the formation of per- and polyfluorinated acids and salts thereof in or on the deposited fluorinated polymer coating. Thereby step IG is carried out after step DF, and from the start of step DF until the end of step IG the object is treated in a substantially oxygen free atmosphere.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for producing an object having a fluorinated polymer coating that does not contain perfluorinated acids and polyfluorinated acids, and their salts.

[0002] Furthermore, the present invention also relates to an object comprising a fluorinated polymer coating that does not contain perfluorinated acids and polyfluorinated acids, and their salts.

Background Art

[0003] Artificial organic compounds such as perfluorinated and polyfluorinated alkyl substances are substances of very high concern (SVHC), and are a large family that has been used in various industries. The literature reports that these have been used as processing additives and surfactants since the 1940s. These compounds have special properties including flame retardancy, as well as oil repellency, antifouling, grease repellency and water repellency, and have generally been used in the manufacture of non-stick cookware, special clothing and textile products, antifouling agents, metal plating and fire extinguishing foams. They are classified into two groups of PFAS: perfluoroalkyl sulfonic acids (PFSA) and perfluorocarboxylic acids (PFCA). PFAS, including these synthetic substances that do not occur naturally in the environment, and their related salts, have already been detected at various concentrations in various types of aqueous environments. This is not at all surprising since certain PFAS are persistent and bioaccumulative. C8-based PFAS are already listed as regulated substances in the EU, and perfluorooctane sulfonic acid (PFOS) was classified as a persistent organic pollutant (POP) in 2009. Similarly, there are regulations, or regulations are planned, to avoid and prohibit perfluorinated acids and polyfluorinated acids, and their salts.

[0004] Plasma polymerization or plasma deposition processes are a thriving research area because they offer diverse pathways for designing materials with controllable functional groups. Due to their unique properties, plasma polymers excel in a wide range of applications, including biomaterials, drug delivery, adhesion, protective coatings, microelectronic devices, oil-water separation, and thin-layer film technologies, thanks to smart coatings such as controllable wettability, self-cleaning, and anti-reflective properties. Furthermore, the use of conventional wet chemical polymerization can lead to adverse effects on polymer coatings, such as non-uniform coatings, and solvent impurities result in coating defects due to the presence of solvents. To avoid these problems, plasma-excited chemical deposition (PECVD) is a polymerization method that utilizes precursors in either liquid or gaseous form, suitable for rapid, pinhole-free, crosslinked dry deposition of polymers.

[0005] Plasma treatment is known to improve the degree of crosslinking of polymers compared to conventional polymerization. Such a fully controlled polymerization method is carried out with the assistance of plasma energy during plasma polymerization, and this plasma energy is used to activate electrons, ions, and radicals. Further explanation of plasma polymerization: A monomer precursor in vapor form is pumped into a vacuum plasma reactor. Then, with the input of energy, excited electrons are generated during a glow discharge, resulting in the decomposition of molecules into free electrons, ions, radicals, and excited molecules. In the later stages, these free radicals and excited molecules recombine, condense, and polymerize on the substrate, and these ions and electrons crosslink with or form chemical bonds with the already deposited polymer, so that the properties of the plasma polymer are determined not only by the precursor but also by the deposition parameters. Films polymerized from perfluorinated precursors and deposited by glow discharge (plasma deposition) are attracting increasingly broad interest. In fact, the vapor deposition method is highly unique, and depending on the selection of monomers and plasma reactor conditions, it offers numerous advantages, including solvent-free operation, room-temperature processing, and control over the thickness of the deposited film, as well as surface texture and surface chemical design. [Overview of the project] [Problems that the invention aims to solve]

[0006] However, it has been found that objects such as fabrics treated by plasma deposition processes using fluorination precursors may still contain significant amounts of perfluorinated and polyfluorinated acids, as well as their salts.

[0007] Therefore, an object of the present invention is to provide a method for producing an object having a fluorinated polymer coating that does not contain perfluorinated acids, polyfluorinated acids, or their salts, deposited by a plasma deposition process, and to provide an object comprising a fluorinated polymer coating that does not contain perfluorinated acids, polyfluorinated acids, or their salts. [Means for solving the problem]

[0008] According to the present invention, this objective is achieved, on the one hand, by a method having the features of claim 1, and on the other hand, by an object such as a fabric having the features of claim 15.

[0009] Preferred embodiments of the present invention are specified in the individual independent claims.

[0010] According to the method of the present invention, in step DF, a fluorinated polymer coating is deposited onto an object by plasma polymerization of a fluorinated precursor monomer. Furthermore, in step IG, the object is exposed to perfluorinated acids and polyfluorinated acids, as well as inhibitory gases that inhibit the formation of their salts, either within or on the deposited fluorinated polymer coating, and step IG is performed after step DF. Furthermore, from the start of step DF to the end of step IG, the object is treated in a substantially oxygen-free atmosphere.

[0011] The fundamental concept of the present invention stems from the discovery that, during the plasma deposition process for producing a fluorinated polymer coating, free radicals and further active components generated during plasma polymerization, when in contact with oxygen during fluorinated polymerization and / or fluorinated coating, become major initiators for forming perfluorinated acids and polyfluorinated acids, as well as their salts.

[0012] The fundamental principle of this formation is expected to be as follows: Radicals play a primary role in the deposition process (radical-dominant plasma) compared to other plasma species such as neutral gas particles, excited states, ions, electrons, and UV. These radicals can further react with monomer molecules, or they can recombine with each other to form a coating. A related number of reactive intermediates, such as excited states, remain in the growing layer, and free radicals, for example, can react with oxygen when the material is exposed to the atmosphere. As a result, perfluorinated acids and polyfluorinated acids, as well as their salts, can be formed in the coating.

[0013] However, according to the present invention, it has been found that if the object to be processed in step DF for plasma deposition of a fluorinated polymer coating after this plasma process is treated with an inhibitory gas, the formation of undesirable perfluorinated acids and polyfluorinated acids, as well as their salts, can be reduced, and ideally prevented. In this regard, during the time from the start of the DF step to the end of the IG step, the object is processed in a substantially oxygen-free atmosphere, and as a result, none of the undesirable components can be generated.

[0014] The functional processes that eliminate the formation of perfluorinated acids and polyfluorinated acids, as well as their salts, are based on the following: Firstly, polymerization of fluorinated monomers should be carried out in an oxygen-free atmosphere, preferably in a vacuum. The addition of oxygenated species or gases reacts directly with the fluorinated components during plasma polymerization to form perfluorinated acids and polyfluorinated acids, as well as salts. In this regard, and as used in the description of the present invention, the term substantially oxygen-free atmosphere can be understood as a state where external oxygen is not available, such as oxygen in ordinary air. However, this does not concern small amounts of oxygen that may be present in the processing chamber due to oxygen gases that may be released from the material of the object itself.

[0015] Secondly, the elimination of perfluorinated and polyfluorinated compounds also heavily depends on a blocking step performed immediately after the deposition of the fluorinated coating. Post-treatment during the blocking step using hydrogen, nitrogen, hydrocarbons, and / or mixtures thereof can inactivate residual reactive intermediates formed in the deposited coating, thus producing a chemically inactive coating such as chained, saturated, etc.

[0016] In process IG, it is preferable that there is no plasma while the object is exposed to the inhibiting gas, that there is plasma at a plasma output of less than half of the plasma output of process DF, or that there is plasma at a maximum plasma output equal to the plasma output of process DF. As previously explained, free radicals and other active components that lead to the formation of perfluorinated acids and polyfluorinated acids, as well as their salts, are generated, at least partially, by the energy supplied by the plasma during the previous plasma deposition in process DF. To further avoid the formation of perfluorinated acids and polyfluorinated acids, as well as their salts, it is advantageous to use a plasma output below the possible level during the IG process.

[0017] In the embodiment, a further step DNF is performed, in which a non-fluorinated polymer coating is deposited onto an object by plasma polymerization of a non-fluorinated precursor monomer, and the DNF is performed before and / or after the DF.

[0018] Conventionally, in the deposition (DF) process for fluorinated polymer coatings, long-chain molecules, such as C8 fluorocarbon (FC) compounds, have been used not only in military formulations but also in coatings to protect objects from everyday substances such as water, oil, fuel, lubricants, cleaning solvents, and other contaminants. However, because long-chain molecules are potentially highly toxic, laws restricting or banning their use have been enacted worldwide. Alternative coatings have been developed and are on the market. In particular, short-chain C6 fluorinated chemical coatings offer performance close to conventional C8-based FC coatings without the high environmental risk.

[0019] The use of C6 FC-based materials still results in environmental pollution due to the presence of trace amounts of perfluorooctanoic acid (PFOA) and its salts, and growing concerns about the persistence and potential bioaccumulation of these substances. Furthermore, the REACH regulation (EU / 784 / 2020), which came into effect on December 3, 2020, permits the use of PFOA while maintaining a threshold of less than 25 ppb (parts per billion). Consequently, there is a general tendency to avoid these chemicals for health reasons.

[0020] The direct process of replacing C6 fluorocarbons (FCs) with ultrashort-chain C3-C1 fluorocarbons (FCs), such as perfluoroalkyl and polyfluoroalkyl materials (PFAS), appears at first glance to be a promising solution. However, it has been observed that problems arise when using plasma nanocoating to deposit these compounds onto the surface of objects such as fabrics, even though these compounds, in principle, provide hydrophobic and oleophobic properties. The thickness of the PFAS-based C3-C1 fluorocarbon (FC) layer during the plasma polymer coating process is significantly thinner than that of the aforementioned C6-C8-based fluorocarbon (FC) layer. Therefore, layers particularly applied to fabrics, such as woven fabrics, yield insufficient layers, and thus only improveable hydrophobic properties. Surprisingly, it has been observed that even a single, thin layer can yield good oleophobic properties.

[0021] Hexamethyldisiloxane (HMDSO) as a non-fluorinated polymer coating is a non-toxic substance and no harmful substances are generated during processing, so it is one of the choices in the industry as a substitute for C6 FC. The vapor pressure of hexamethyldisiloxane is suitable and it is widely used as a precursor monomer in plasma processes. Carbon-rich plasma-polymerized HMDSO (pp-HMDSO) derived from pure HMDSO exhibits promising mechanical properties such as low internal stress, good adhesion, and excellent hydrophobic barrier performance. The water resistance achieved by pp-HMDSO coating is promising but does not provide any oleophobic properties.

[0022] Therefore, according to this embodiment, in step DNF, it is proposed to use in combination a non-fluorinated polymer coating and the conventional fluorinated polymer coating in step DF using C6, preferably C3 - C1 fluorocarbons. Thus, the order of the two steps can be arbitrary, but it is preferred that the DNF step is performed before the DF step.

[0023] The plasma deposition process for depositing the fluorinated polymer coating in step DF and / or the plasma deposition process for depositing the non-fluorinated polymer coating in step DNF is preferably a low-pressure plasma process and / or an atmospheric pressure plasma process under a protective atmosphere.

[0024] The low-pressure plasma coating technology is also known as the plasma-enhanced chemical vapor deposition (PECVD) method. Cold plasma is used in this technology. Therefore, this technology is suitable for heat-sensitive polymer materials such as monofilament mesh and composite membranes. Using PECVD, a crosslinked polymer network with functional groups incorporated into the network can be deposited, and thus, very long-term stability of the modified surface can be obtained. The fluorinated coating does not decompose into PFAS.

[0025] The inhibitory gas in engineering IG is preferably hydrogen, nitrogen, hydrocarbon, a mixture thereof, and / or a gas mixture containing any of the above gases. These gases or their mixtures have surprisingly been found to be effective in inhibiting additional active components that result in the formation of free radicals, as well as perfluorinated acids and polyfluorinated acids, and their salts.

[0026] The inhibition process has been shown to play an important role in eliminating perfluorinated acids and polyfluorinated acids, and their salts. The inhibition process can be carried out on the fluorinated coating surface using hydrogen, nitrogen and hydrogen carbonate gas in a vacuum chamber immediately after the fluorine deposition process without taking the object out into the atmosphere. Free radicals, oxygenated species, charged particles, etc. are formed on the surface during the plasma polymerization of the fluorinated precursor. The inhibition process neutralizes such reactive components, and thus perfluorinated compounds and polyfluorinated compounds are effectively removed when the coated object is exposed to the inhibitory gas. This is emphasized by the numbers shown in Table 1, as the inhibition process has been shown to dramatically reduce the amount of perfluoroalkyl derivatives and polyfluoroalkyl derivatives.

[0027]

Table 1

[0028] Various deposition conditions can be used to reduce the concentration of perfluorinated substances and polyfluorinated substances. Depending on the process parameters, especially the plasma output, the PFC compounds vary. The higher the energy input, the higher the plasma dissociation / fragmentation, which contributes to a greater amount of PFC compounds being produced in the growing film due to the higher energy ion bombardment. On the other hand, it is difficult to obtain good oil repellency with a very low energy input. According to the present invention, in order to obtain suitable coating characteristics without having PFC compounds, the plasma output is 1 cm during process DF and / or process DNF 2Less than 1W per electrode surface, preferably 1cm 2 Less than 500 mW per electrode surface, or more preferably 1 cm 2 It was found that the power consumption per electrode surface must be less than 200 mW.

[0029] [Table 2]

[0030] The fluorinated polymer coating in step DF may be carried out using perfluorocarbons or perfluorinated hydrocarbons, and / or the non-fluorinated polymer coating in step DNF may be organosilanes, siloxanes and / or Hydrocarbons This may also be done using a precursor.

[0031] In one embodiment, the method may include an additional pretreatment step PT of the object using atmospheric pressure or low-pressure plasma with an inert gas and / or reactive gas, wherein step PT is preferably performed as a first step before steps DNF and / or DF. The PT step may be performed to clean the surface of the object to be treated, thereby enabling more efficient film deposition. In this regard, the PT step may preferably be performed as a first step before the DNF and DF steps. However, depending on the object being treated, it may also be advantageous to perform the PT step before the DNF and / or DF steps each time.

[0032] After all other processes have been completed, and especially if there is no oxygen between different processes, it is sufficient to perform the IG process only once. However, it is advantageous to perform the IG process immediately after each DF, PT, and / or DNF process in order to deactivate plasma-based reactive substances, particles, or components that form on the coated object during the plasma deposition of the aforementioned DF, PT, and / or DNF processes. In this way, the inhibition of undesirable substances is improved. Similarly, free radicals and other active substances from the previous coating process are not coated in the subsequent coating process and are inhibited between the preceding and succeeding coating processes.

[0033] Depending on the material used to be deposited in step DF, the fluorinated polymer coating deposited on the object may have a thickness of 5 nm to 300 nm, and / or the non-fluorinated polymer coating deposited on the object in step DNF may have a thickness of 30 nm to 700 nm. Generally, deposition in steps DF and DNF should result in an improvement in the surface properties of the object. Specifically, the objective is to provide an object having hydrophobic and / or oleophobic coatings or surface properties. That is, non-fluorinated polymer coatings do not achieve the same good properties as fluorinated polymer coatings, and therefore, it is advantageous for the coating thickness of the non-fluorinated polymer coating to be greater than that of the fluorinated polymer coating.

[0034] In principle, there is no upper or lower limit to the plasma output during the deposition process DF and / or DNF. However, the plasma output is limited to 1 cm between the DF and / or DNF processes. 2 Less than 1W per electrode surface, preferably 1cm 2 Less than 500 mW per electrode surface, or more preferably 1 cm 2The power is preferably less than 200 mW per electrode surface. This appears to be a good compromise between sufficient polymer deposition, which is improved by higher energy, and the generation of undesirable components, which result in perfluorinated acids and polyfluorinated acids, as well as their salts.

[0035] The material preferably includes polymer materials such as mesh fabrics, woven fabrics, knitted fabrics, nonwoven fabrics, meltblown nonwoven fabrics, spunbond nonwoven fabrics, membranes, composite membranes, and combinations thereof. When woven materials are used, monofilament yarns are particularly preferred.

[0036] In detail, this object is one or more of the following substances, or a combination thereof: polyvinylidene chloride (PVDC), polyvinylidene fluoride (PVDF), polyhexamethylene adipoamide (PA6.6), polydodecaneamide (PA12), polypropylene (PP), polycaproamide (PA6), polyethylene terephthalate (PET), ethylene monochlorotrifluoroethylene (E-CTFE), ethylene tetrafluoroethylene (ETFE), polyethylene (PE), polyoxymethylene (POM), polycaprolactone (PCL), polysulfone (PS), polyvinylidene fluoride (PVDF), chitosan (CH), polyvinyl butyral (PVB). , 1-dodecyltrimethylammonium bromide (DTAB), chlorhexidine (CHX), benzyltrimethylammonium bromide (BTAB), polyacrylate, polyethylene (PE), high-density PE, fluoroethylene propylene (FEP), two-component (PA6 / PA12), polybutylene terephthalate (PBT), polyether ether ketone (PEEK), perfluoroalkoxy (PFA), polyacrylonitrile (acrylic fiber) (PAN), two-component, PET flame retardant (PET / PBT), polyundecaneamide (PA11), polytetrafluoroethylene (PTFE), polyphenylene sulfide (PPS), polyhexamethylene sebacinamide (PA6).10) It can be made from and / or may contain these materials: aramid (AR), polyethylene naphthalate (PEN), polyamide carbon fiber (PA / CF), polyester carbon fiber (PET / CF), polyester staple fiber / metal fiber (PET / MT), carbon fiber (CF), copper (CU), polyimide (P84), copper / silver (CU / AG), polycarbonate (PC), aliphatic polyamide, aromatic polyamide, polyurethane (PU), polyvinyl alcohol (PVA), polylactide (PLA), polybenzimidazole (PBI), polyethylene oxide (PEO), poly(butylene terephthalate), polyvinyl chloride (PVC), cellulose, cellulose acetate (CA), polypropylene (PP), PVA / silica, PAN / TiO2, PETFE polyetherimide (PEI), polyaniline, poly(ethylene naphthalate), styrene-butadiene rubber, polystyrene, poly(vinylbutylene), and polymethyl methacrylate (PMMA).

[0037] It can be understood that no object formed in any manufacturing process can be 100% free of a particular substance. Therefore, according to the present invention, the fluorinated coating should be understood to be free of perfluorinated acids and polyfluorinated acids, as well as their salts, in accordance with standard 100 of OEKO-TEX and / or DIN CEN / TS15968:2010.

[0038] In principle, the processes PT, DNF, DF, and IG described above can be performed in any order, and it is possible to perform some processes more than once. In one preferred embodiment, the processes are performed in the following order: process PT, process DNF, process DF, process IG, and optionally, process DNF again. It is recognized that processing an object to which an oleophobic and hydrophobic coating will be provided by the processes in the order specified above yields excellent results. [Effects of the Invention]

[0039] According to the present invention, it is possible to produce an object comprising a fluorinated polymer coating formed on the object, which does not contain perfluorinated acids and polyfluorinated acids, or their salts. This object can be used in a multitude of applications, for example, as protective vents in portable devices: acoustic vents, ventilation filters, fuel filtration, water separation, clothing, packaging, buildings and electronic seals / circuit boards, shoes, wound dressings or as filters for facial masks. The present invention further covers electronic or electrical equipment such as mobile phones, portable media players, high-fidelity devices, tablets, laptops, all kinds of portable devices, and televisions. The object according to the present invention can be used as a ventilation barrier medium for a variety of ventilation applications in healthcare, such as intravenous fluid / transfusion / blood filters, mattresses, pillows, duvets, bedding, ventilation filters for (electrical) equipment (indoor and / or outdoor), (surgical) masks, (surgical) coats, intravenous inline filter sets, and pressurized filtration devices, especially in medical devices, as well as for indoor ventilation and industrial applications.

[0040] The present invention is further described by preferred exemplary embodiments schematically illustrated in the accompanying drawings below. [Brief explanation of the drawing]

[0041] [Figure 1] This figure shows a combination of schematic flowcharts of the method of the present invention, including examples of various vapor-deposited films on object surfaces. [Figure 2] This is a schematic diagram of a method for producing polymer composite fabrics. [Figure 3] This is a schematic diagram showing a comparison of the contact angles of DF / DNF coated articles and C6 coated articles. [Modes for carrying out the invention]

[0042] The left side of Figure 1 shows a schematic flow chart including several steps according to the present invention. The right side of Figure 1 illustrates a deposited layer on the surface of an object.

[0043] According to this embodiment, first, step PT is performed. In this step, the surface of an object is plasma pre-treated to prepare it as a substrate for depositing a different subsequent layer onto its surface. The plasma treatment is preferably performed in a sealed chamber under a low-pressure atmosphere. The purpose of this treatment is to clean the surface of the substrate or object so that the subsequent polymer can be deposited well. Depending on the power used, the plasma treatment can also roughen the surface of the substrate, resulting in better adhesion of the subsequent layer. Sometimes, this roughening can be considered as the creation of microscopic grooves into the material of the substrate.

[0044] Following the PT process, a DNF process is performed to deposit a non-fluorinated polymer coating onto the object surface. Preferably, the object to be coated is maintained in a low-pressure or vacuum chamber throughout the entire processing process.

[0045] Non-fluorinated polymer coatings can be made based on organosilanes (such as trimethylsilane), siloxanes (such as hexamethyldisiloxane and tetramethylsilane), hydrocarbons (such as methane, ethane, and acetylene), and mixtures thereof.

[0046] As can be seen on the right side of Figure 1, after cleaning in process PT, the first vapor deposition layer DNF is applied to the substrate surface.

[0047] Following the DNF process, process DF is performed, where a fluorinated polymer coating is deposited onto the surface of the previous DNF layer. These two layers, combined in a very simple manner as shown only on the right side of Figure 1, ensure that the entire surface of the substrate is coated. Typically, the deposition of the layers may not be uniform in this manner.

[0048] Fluorinated polymer coating in the DF process can be carried out based on ultrashort-chain perfluorocarbons (hexafluoropropene, octafluoropropene, trifluoropropene, pentafluoropropene, etc.), fluorinated surfactants, C1 / C2 / C3 difluoride carbon-based acrylic monomers, and fluorinated acrylates (perfluorodimethylcyclohexane).

[0049] Following the DF process, process IG is performed, in which the previously double-coated substrate, and thus the two coatings, are exposed to an inhibitory gas. The purpose of this exposure is to inhibit the formation of perfluorinated and polyfluorinated acids, as well as their salts, and the coated object should be brought into contact with oxygen.

[0050] In other words, post-treatment during the blocking step using hydrogen, nitrogen, hydrocarbons, and / or mixtures thereof can inactivate residual reactive intermediates formed in the deposited coating, thus producing a chemically inert coating due to chaining, saturation, etc.

[0051] According to the present invention, it may be essential that the treated coated object be handled in a substantially oxygen-free atmosphere until the process IG is carried out. According to the present invention, it may be understood that, in a sense, all processing and deposition is carried out in a chamber having a vacuum atmosphere, a low-pressure atmosphere, or an atmosphere that does not contain external oxygen present in the air. If the chamber is under vacuum, degassing of water vapor containing oxygenated substances from the substrate may occur, and therefore it is difficult to achieve a 100% oxygen-free atmosphere. However, these small amounts of oxygenated substances do not have any negative effect and inhibit the formation of perfluorinated acids and polyfluorinated acids, as well as their salts.

[0052] After the IG process is completed, the coated object can, in principle, be used or sent for further processing.

[0053] However, in this embodiment, an additional coating is provided in anticipation of an additional DNF step to further improve the properties of the object. In connection with this, it can be emphasized that because a non-fluorinated polymer is used during this step, the generation of important radicals and active substances that may result in perfluorinated acids and polyfluorinated acids, as well as their salts, when combined with oxygen does not occur, and as a result, this step can be carried out even under atmospheric pressure containing oxygen.

[0054] As can be seen simply on the right side of Figure 1, the object coated by this method has a fluorinated polymer coating sandwiched between two non-fluorinated polymer coatings.

[0055] In general, the object to be coated can be of any type. Preferably, the method of the present invention is used to coat a composite film made of one or more carrier layers and one or more films. Further examples of this case are illustrated in the following figures.

[0056] The scheme in Figure 2 illustrates an example of a manufacturing process for a polymer fabric, such as a composite, that includes a carrier layer. The collected substrate (upper figure) is shown, with an electrospinning film formed on its surface (first production step). The electrospinning film is formed in accordance with generally known concepts, which are further described below.

[0057] In the second step, the formed film is transferred to a carrier layer and bonded (bonding 1), and the original collection substrate on which the electrospinning film was formed is optionally removed (removal of collection substrate). As shown in the diagram, the carrier layer can be a mesh or a fabric.

[0058] In some cases, a second bonding (bond 2) with a second outer layer is performed, after which any calendering process can be carried out. Thus, the electrospinned film can be optionally placed between two identical or different layers to form a sandwich structure. The second outer layer can be provided, for example, as a mesh, lining, or nonwoven material. Finally, the plasma coating of the present invention is applied to at least one carrier layer and film.

[0059] A first layer that achieves only hydrophobic properties, and a subsequent layer that achieves both hydrophobic and oleophobic properties, may be deposited. The first layer can be pp-HMDSO, fluorine-doped HMDSO, DLC, or a fluorine-doped DLC layer. Further outer layers may be layers based on PFAS containing one, two, or three C atoms, and / or layers based on PFPE.

[0060] Electrospinning Methods for fabricating nanofiber webs are illustrated in WO2006 / 131081 and WO2008 / 106903.

[0061] In short, the electrospinning process uses a high voltage to generate a charged jet of a polymer solution or molten material from a pipette. The jet of solution volatilizes or solidifies before reaching a collection screen and is collected as a web of interconnected tiny fibers. One electrode is placed in the spinning solution / molten material, and the other electrode is attached to the collector. In most cases, the collector is simply grounded. An electric field is applied to the end of a capillary tube containing the fluid solution, which is held in place by its surface tension. This induces a charge on the surface of the liquid. Mutual charge repulsion and the contraction of the surface charge to the counter electrode create a force that directly opposes the surface tension. As the strength of the electric field increases, the hemispherical surface of the fluid at the tip of the capillary tube stretches to form a conical shape known as a Taylor cone. At even higher electric field levels, the repulsive electrostatic force reaches a critical value where it overcomes the surface tension, and the charged jet of fluid is ejected from the tip of the Taylor cone. The jet of released polymer solution undergoes unstable and elongation processes, which allow the jet to become very long and thin. During this time, the solvent evaporates, leaving behind charged polymer fibers. In the case of a molten material, the released jet solidifies as it moves through the air.

[0062] Bonding method Various bonding technologies are available. These include hot-melt gravure lamination, ultrasonic bonding, dip bonding, UFD fiber spray (hot-melt), and spanweb bonding.

[0063] Hot melt gravure lamination technology is industrially established for in-line processes. Therefore, it is possible to perform two-step bonding on a single line for a "sandwich" type film. This involves using a multi-purpose hot melt lamination and coating system, which consists of gravure printing rollers for dot coating, revolver ejection heads (positive / positive or negative / negative), coating rollers, laminating rollers, and reverse pressure rollers.

[0064] Gravure printing rollers are used for dot coating with adhesives, allowing the use of two different PU-based reactive adhesives (one for PU e-spinning films and the other for PA6 films). High bonding strength can be achieved with an air permeability loss of approximately 15-25%. The adhesive must be carefully selected to avoid problems between the end application of the film (compatibility, physical and chemical suitability, medical-grade and food-grade, etc.). Curing of the material is observed for the adhesive.

[0065] Before the electrospinning process, dip bonding (chemical bonding) can be used to pre-treat the support, which is sometimes preferable. Similarly, it eliminates the need for additional process steps for bonding, which is a major advantage. Then, the lamination of the two layers can be used for a second bonding, such as hot melt, span-web, UFD, etc., to form multilayer pores.

[0066] UFD is a fiber spraying technology and the most advanced technology compared to hot melt adhesive applicators. It applies laminate plate technology (LPT) to generate filament strands of adhesive. Heated air is used to stretch these strands, laying them horizontally in random or ordered patterns. Often, by using UFD technology, the amount of adhesive used can be reduced by 20-50% without negatively impacting bond strength or durability by applying the adhesive with high precision. A non-contact mode is available, which reduces the likelihood of damage to e-spun fibers during lamination. UFD technology is a cleaner process than hot melt gravure printing lamination.

[0067] Spunweb bonding technology yields a three-dimensional structure rather than a film with a closed surface. Due to its open structure, the resulting laminate is even more flexible and breathable. The web can be fabricated from various materials, including copolyamides, copolyesters, copolyolefins, and polyurethanes. Spunweb technology is a very simple process. The three main parameters to consider during lamination are temperature, pressure, and time.

[0068] Calendar Calendering is used on the surface of materials such as fabrics, meshes, and laminated ventilated materials to obtain a smoother and thinner material, which then passes between or under rollers at high temperature and pressure. The size and shape of the pores may be affected depending on the calendering conditions.

[0069] Plasma PECVD Plasma treatment of textile products or other materials can be applied as a finishing process for textile products, i.e., for industrial and medical textile products, as well as for composite materials, to improve their surface properties such as water repellency and oil repellency. This is also possible for other materials and small objects. Compared to conventional wet chemical finishing of textile products, plasma technology offers advantages in terms of environmental issues. In the case of PECVD treatment, for example, improvements in adhesion properties, increased hydrophilicity, introduction of special functional groups to the surface, or modification of the surface geometry can be obtained.

[0070] Plasma polymerization, commonly known as PECVD, allows for the deposition of extremely thin polymer layers (nanoscale) onto a substrate surface. The layer is formed by the polymerization of an organic precursor gas, which polymerizes directly on the substrate surface. In contrast to conventional polymerization, plasma polymerization can utilize any monomer gas or vapor, without limiting its reactivity. Plasma polymers exhibit unconventional polymerization behavior, with branched, random end chains and a high degree of crosslinking.

[0071] The bulk structure of plasma polymers is completely irregular and differs significantly from the bulk structure of conventional polymers. Plasma polymer coatings (nano-thin films) differ from conventional polymers in that they have a high density of functional groups per unit volume, a highly crosslinkable and branched plasma polymer network, are nanometer-thick coatings, have high adhesion to the substrate, and the bulk properties of the substrate remain unchanged. As a result, the substrate can be a polymer fabric.

[0072] Plasma treatment, in the case of fabrics, can be performed in a roll-to-roll system within a plasma chamber having multiple rollers and / or expanders, which can be operated by radio waves preferably at about 13 MHz to 14 MHz, preferably about 13.5 MHz, or by a direct current (DC) power supply. All the preferred steps described earlier, DF, DNF, PT, and IG, are performed within this plasma chamber.

[0073] Performance Examples The following describes the performance and properties of fabrics coated according to the present invention, including DF coating based on C3 fluorinated chemicals. [Examples]

[0074] The contact angles of four liquids were measured on two different articles in accordance with DIN55660-2. One article was coated with a combination of a C3-based coating (DF), a DNF coating agent, and an IG process, while the other was coated with a C6-based FC coating (benchmark). As can be seen in Figure 3, similar hydrophobicity and oleophobicity were achieved even with the ultrashort-chain, environmentally friendly C3-based coating (DF) compared to the C6-based coating. Furthermore, a slight increase in the contact angle was found in article 3A07-0019-115-XX compared to article 3A07-0025-158-XX. This can be explained as follows: higher fabric density (smaller mesh openings) and finer filaments in 3A07-0019-115-XX contribute to superior repulsion. [Examples]

[0075] To ensure that the plasma coating (DN, DNF, and IG processes) adheres securely and sufficiently to the substrate, an internal cleaning test is performed at a temperature of 40°C for 47 minutes. As shown in Table 3, the coating exhibits high cleaning resistance. A slight decrease in the contact angle using three different liquids, measured in accordance with DIN55660-2, demonstrates high coating adhesion to the object. The oleophobicity of the object after cleaning was also evaluated in accordance with AATCC118 using eight different liquid oils, and the results showed no change in oleophobicity after cleaning. Therefore, based on the present invention, it is possible to obtain a robust and reliable coating on polymer fabric surfaces with excellent hydrophobic and oleophobic properties.

[0076] [Table 3] [Examples]

[0077] To evaluate the water separation efficiency, DNF and DF coated polyester articles were tested in accordance with the ISO / TS16332 standard. As can be seen in Table 4, even when using the C3-based environmentally friendly coating, comparable results of over 90% water separation efficiency were obtained compared to the C6-based coating (benchmark).

[0078] [Table 4]

[0079] In addition to performance tests, endotoxin and blood compatibility tests were similarly performed on the fabrics coated according to the present invention.

[0080] Endotoxin testing is performed to determine the potential of a product for medical use. Endotoxin limits are based on the Pharmacopoeia (EP10, January 2020 and United States Pharmacopoeia 42, May 1, 2019). <85> The calculation is performed in accordance with the standard. Both the DF and DNF coated articles contained endotoxins below the limit and passed this test.

[0081] Blood compatibility of substances that come into contact with blood is also one of the most important diagnostic criteria for medical applications. The interaction between newly developed coating materials and blood was extensively analyzed in accordance with ISO 10993-4 and ISO 10993-12 to prevent activation and destruction of blood components during application. The blood compatibility analysis of the coated articles is summarized in Table 5 below, and all coated articles passed this test.

[0082] [Table 5]

[0083] To meet biocompatibility requirements for medical applications, cytotoxicity tests were conducted on DNF and DF-coated polyester articles in accordance with ISO 10993-5 to determine the extent to which the coated articles could be damaged or even cause death of human cells. Optical evaluations of cell morphology and cell viability are presented in Table 6. The coatings were found to inhibit cell growth to almost no extent. Cell viability with respect to the coatings was also very good, and therefore the coatings meet the requirements of ISO 10993-5.

[0084] [Table 6]

[0085] The present invention provides a method for producing an object having a fluorinated polymer coating that does not contain perfluorinated acids, polyfluorinated acids, or their salts, deposited by a plasma deposition process, and also provides an object containing a fluorinated polymer coating that does not contain perfluorinated acids, polyfluorinated acids, or their salts.

Claims

1. A method for producing an object having a fluorinated polymer coating that does not contain perfluorinated acids, polyfluorinated acids, or salts thereof, Step DF involves depositing the fluorinated polymer coating onto the object by plasma polymerization of the fluorinated precursor monomer, Step IG involves exposing the object to a perfluorinated acid and a polyfluorinated acid, as well as an inhibitory gas that inhibits the formation of their salts, within or on the deposited fluorinated polymer coating. Includes, The aforementioned object includes polymer materials such as mesh fabrics, woven fabrics, knitted fabrics, nonwoven fabrics, meltblown nonwoven fabrics, spunbond nonwoven fabrics, membranes, composite membranes, and combinations thereof. The inhibiting gas is a gas mixture containing hydrogen, hydrocarbons, mixtures thereof, and / or any of the above gases. The aforementioned process IG is performed immediately after the aforementioned process DF. A method wherein the object is processed in a substantially oxygen-free atmosphere from the start of step DF to the end of step IG.

2. The method according to claim 1, characterized in that, in step IG, there is no plasma while the object is exposed to the inhibiting gas, or there is plasma with a plasma output of less than half of the plasma output of step DF.

3. The method according to claim 1, characterized in that the inhibiting gas is hydrogen, hydrocarbons, or a mixture thereof.

4. A method for producing an object having a fluorinated polymer coating that does not contain perfluorinated acids, polyfluorinated acids, or salts thereof, Step DF involves depositing the fluorinated polymer coating onto the object by plasma polymerization of the fluorinated precursor monomer, Step IG involves exposing the object to a perfluorinated acid and a polyfluorinated acid, as well as an inhibitory gas that inhibits the formation of their salts, within or on the deposited fluorinated polymer coating. A DNF step involves depositing a non-fluorinated polymer coating onto the object by plasma polymerization of a non-fluorinated precursor monomer, Includes, The inhibiting gas is a gas mixture containing hydrogen, hydrocarbons, mixtures thereof, and / or any of the above gases. The aforementioned process IG is performed immediately after the aforementioned process DF. The aforementioned DNF is performed before and / or after the aforementioned DF. A method wherein the object is processed in a substantially oxygen-free atmosphere from the start of step DF to the end of step IG.

5. The method according to 1 or 4, characterized in that the plasma deposition process for depositing the fluorinated polymer coating in step DF and / or the plasma deposition process for depositing the non-fluorinated polymer coating in step DNF is a low-pressure plasma process and / or an atmospheric pressure plasma process under a protective atmosphere.

6. The method according to claim 1, characterized in that the fluorinated polymer coating in step DF is carried out using perfluorocarbon or perfluorinated hydrocarbon.

7. The method according to claim 4, characterized in that the non-fluorinated polymer coating in the DNF step is carried out using an organosilane, siloxane and / or hydrocarbon precursor.

8. The process further includes a pretreatment step PT of the object using atmospheric pressure or low-pressure plasma with an inert gas and / or reactive gas, The method according to 4, characterized in that the aforementioned process PT is performed before process DNF and / or DF.

9. The method according to 1, 4, or 8, characterized in that, after performing the DF, PT, and / or DNF steps, the IG step is performed in particular, directly each time, in order to deactivate plasma-based reactive species formed on the coated object during the plasma deposition of the DF, PT, and / or DNF steps.

10. In step DF, the fluorinated polymer coating deposited on the object has a thickness of 5 nm to 300 nm, and / or The method according to 1 or 4, characterized in that the non-fluorinated polymer coating deposited on the object in the DNF step has a thickness of 30 nm to 700 nm.

11. The plasma output is 1 cm between the process DF and / or the process DNF. ２ The method according to 1 or 4, characterized in that the power per electrode surface is less than 1W.

12. The method according to 4, characterized in that the object includes polymer materials such as mesh fabrics, woven fabrics, knitted fabrics, nonwoven fabrics, meltblown nonwoven fabrics, spunbond nonwoven fabrics, membranes, composite membranes, and combinations thereof.

13. The method according to claim 1, characterized in that the fluorinated polymer coating does not contain perfluorinated acids and polyfluorinated acids, or salts thereof, in accordance with standard 100 of OEKO-TEX and / or DIN CEN / TS 15968:2010.

14. A DNF step involves depositing a non-fluorinated polymer coating onto the object by plasma polymerization of a non-fluorinated precursor monomer, A pretreatment step PT of the object using atmospheric pressure or low-pressure plasma with an inert gas and / or reactive gas, It further includes, The process is as follows:

1. Process PT 2. Process DNF 3. Process DF 4. Process IG and, if applicable 5. Again, process DNF The method according to claim 1, characterized in that it is carried out in the following order.

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