Evidence of anti-creak treatment of foam elements with a fluorescent anti-creak agent

Abstract

Method for detecting a treatment of a foam element with an anti-creaking agent, comprising the steps of • Providing the foam element; • Providing a fluorescent anti-creaking agent comprising a lubricant used as an anti-creaking agent and a fluorescent marker substance, wherein the fluorescent marker substance is fluorescein, wherein the marker substance emits visible fluorescent radiation upon irradiation with ultraviolet light, • Applying the fluorescent anti-squeak agent to the foam element, • Irradiating the foam element on which the fluorescent anti-squeak agent is applied with ultraviolet light, • Detection and evaluation of the fluorescent radiation emitted by the coated foam element by irradiation with ultraviolet light.

Description

[0001] The invention relates to the detection of a treatment of foam elements with anti-squeak agents. In particular, the invention relates to a method for detecting an anti-squeak agent treatment of foam elements, particularly those used in vehicle seats.

[0002] The background to the invention is that creaking noises occur in motor vehicles. So-called creaking noises arise due to the relative movement of two surfaces in contact, such as between a seat cover and a foam element in vehicles, or between a seat support or seat base and the foam element arranged on it.

[0003] The publication DE 195 17 702 C1 describes that upholstery elements are made of foam, particularly polyurethane foam. Due to its open cell structure, polyurethane foam has blunt surfaces that make subsequent covering with fabric difficult, resulting in significant friction. It also shows that foam covered with fabric or leather emits squeaking noises (so-called "creaking") under load due to the constant friction. The publication further reports that there is a risk of soiling of the covering materials during the manufacture of upholstered parts in the automotive industry. To solve these problems, the publication proposes the use of emulsifiers as lubricants for covering foamed molded bodies, particularly upholstery elements, with polyurethane foam. An applied lubricant film remains on the foamed molded body (upholstery element).It acts as a lubricant when covering the foam core, thus significantly facilitating the process. It also remains on the contact surfaces between the foam core and the cover fabric, effectively and permanently reducing friction, preventing squeaking noises from occurring during use of the upholstery elements.

[0004] The publication DE 102 55 453 A1 discloses a low-cost manufacturing process for a foam molded body. This process is characterized by the fact that, with the aid of a foaming tool, not only the foam body itself is produced, but also, in the same process, a coating made of a wear-resistant and noise-reducing plastic material that is integrally bonded to the foam body in defined surface areas. This eliminates the need for manual insertion of a prefabricated fabric cut and the subsequent spraying of an anti-squeak agent, resulting in a significant simplification of production, which is particularly advantageous in the large-scale production of motor vehicle seat parts or motor vehicle backrest upholstery.

[0005] The document DE 10 2013 007 335 A1 shows a method for reducing creaking noises that arise during the relative movement of two contacting surface areas of a foam body arranged on at least one support or a subframe, in which the at least one support is coated with a corrosion protection coating, wherein it is provided that at least the part of the coated surface of the at least one support, which in its surface area comes into contact with the surface area of ​​the foam body arranged on the at least one support in a contact area, is provided with a surface structure by a surface treatment before coating, the support surface roughness of which is selected depending on the layer thickness of the subsequent coating such that a subsequent coating of the surface of the at least one support has a coating surface roughness,in which friction effects caused by loading of the foam body in the contact area with the at least one carrier do not generate any noise.

[0006] Reference is also made to document DE 10 2006 060 477 A1. This document describes a vehicle seat with a seat shell and a leather seat cover. To prevent creaking noises between the seat cover and the seat shell, an insert made of a single-layer knitted textile band is used between the seat cover and the seat shell.

[0007] Finally, DE 100 35 507 A1 describes a method for reducing creaking noises that arise during the relative movement of two contacting surface areas. In this method, a thin layer is deposited on one or both of the contacting surface areas using plasma deposition. This thin layer exhibits a lower adhesion component and a lower deformation component of the friction force than the uncoated surface areas. This method allows creaking noises to be reduced or completely suppressed without altering the visual appearance of the underlying surface areas.

[0008] In summary, it is known that • to apply a lubricant film to a foamed molded body (cushion element) or • to manufacture a foam body with a cover made of a wear-resistant and noise-reducing plastic material integrally connected to it, or • reduce friction effects by changing the surface roughness of the materials in contact, or • to place an insert between the seat cover and the seat shell or to apply a thin layer to surface areas by means of plasma deposition.

[0009] It is also known that foam elements are treated with colored or dyed anti-squeak agents. The anti-squeak agent is sprayed onto the foam element, for example, using a spray gun. Conventional anti-squeak agents, for example, are colored blue or have a blue color to make the anti-squeak treatment visible and thus verifiable.

[0010] However, colored anti-squeak agents lead to adverse soiling of the seat cover, especially when the seat cover is pulled onto the foam element.

[0011] Furthermore, reference is made to the documents DE 10 2004 058 434 B4, DE 10 2015 101 331 A1, JP 2013-226 814 A and JP 2017-179 135 A. The document DE 10 2004 058 434 B4 describes an add-on part in the interior of motor vehicles, which has contact surfaces with at least one other attachment or component and in which relative movements occur at the contact surfaces, wherein the contact surface of one of the attachments or components involved is coated with a virtually abrasion-free, low-friction coating by applying a varnish which is formed from a solid lubricant, a binder and a solvent, wherein the varnish contains polyethylene oxide combined with a fluoropolymer and synthetic wax.

[0012] DE 10 2006 009 653 A1 relates to a wiper blade, in particular for windscreen wipers of a motor vehicle, and to a method for determining the layer thickness of a coating of a wiper blade.

[0013] EP 2 932 245 B1 relates generally to insertion devices for inserting intraocular lenses into a patient's eye during vision correction surgery and, more particularly, to lens insertion cartridges and methods for manufacturing cartridges.

[0014] DE 10 2016 125 471 A1 relates to a method for sorting offcuts or punching waste from metal alloys, wherein the surface of the metal sheet is coated with a carrier material.

[0015] JP H 10320739 A relates to a magnetic recording medium having a magnetic layer formed on a non-magnetic support and a lubricant applied to the surface of the magnetic layer, and a method for producing the same. Furthermore, the invention relates to a magnetic recording medium in which a material exhibiting fluorescence or an absorption spectrum upon light irradiation is contained in a lubricant, and a layer thickness of the lubricant is precisely defined, and a method for producing the same.

[0016] The treatment of foam elements with a conventional colorless anti-creaking agent is therefore the starting point of the invention.

[0017] The problem underlying the invention is therefore that when applying colorless anti-creak agent to seat foam elements, uniform wetting with the anti-creak agent cannot be reliably guaranteed, since the application cannot be visually checked due to the colorlessness of the anti-creak agent.

[0018] Based on this prior art, the invention is therefore based on the object of creating a means of detection or control for the treatment / application of a foam element, in particular for a vehicle seat, with an essentially colourless anti-creaking agent.

[0019] Accordingly, the invention is intended to provide a method which enables treatment and detection of an anti-creaking drug treatment, so that the quality of the treatment is increased, in particular by eliminating possible contamination, and the quality of the treatment is also verifiable.

[0020] The invention is based on the treatment of foam elements with an anti-squeak agent, which is applied to the foam element. Anti-squeak agents prevent or at least reduce the generation of noise that typically results from the relative movement of two surfaces in contact, such as between a seat cover and a foam element in vehicles. Anti-squeak agents, also known as lubricants, typically have an oil-like consistency.

[0021] The method according to the invention for detecting a treatment of a foam element with an anti-creaking agent is characterized by the following steps: • Providing the foam element, • Providing a fluorescent anti-creaking agent comprising a lubricant used as an anti-creaking agent and a fluorescent marker substance, wherein the fluorescent marker substance is fluorescein, wherein the marker substance emits visible fluorescent radiation upon irradiation with ultraviolet light, • Applying the fluorescent anti-squeak agent to the foam element, • Irradiating the foam element on which the fluorescent anti-squeak agent is applied with ultraviolet light, • Detection and evaluation of the fluorescent radiation emitted by the coated foam element by irradiation with ultraviolet light.

[0022] According to the inventive concept, it is provided that a colorless fluorescent anti-creaking agent is applied to the provided foam element.

[0023] A known lubricant has previously been used as an anti-creaking agent. The anti-creaking agent according to the invention now contains fluorescent pigments that emit visible light when exposed to ultraviolet light (i.e., UV light), making the fluorescent pigments and thus the fluorescent anti-creaking agent visible. In simple terms, one could also speak of a lubricant to which the marking substance containing fluorescent pigments has been added, as will be explained below.

[0024] It is intended that the provision of the fluorescent anti-creaking agent is carried out by adding the marking substance directly in a powdered state or indirectly in a liquid state to the anti-creaking agent in a predetermined quantitative ratio, wherein the powdered marking substance is mixed with a liquid to form an emulsion in the case of indirect addition before the emulsion is added to the anti-creaking agent in the predetermined quantitative ratio.

[0025] According to the invention, the fluorescent pigments are added / mixed to the preferably colorless anti-squeak agent.

[0026] Fluorescent pigments are those that can be excited by UV light in such a way that they emit visible light when exposed to UV light, making them visible to the human eye and conventional camera systems. By adding fluorescent pigments to the lubricant, the fluorescent anti-creaking agent is ultimately created.

[0027] The step of irradiating the foam element, to which the fluorescent anti-squeak agent is applied, is carried out with UV light. The UV light excites the fluorescent pigments so that they emit visible light.

[0028] Accordingly, a further step is provided in such a way that visible light emissions from the foam element of the fluorescent pigments of the anti-creaking agent are recorded and evaluated.

[0029] The method provided by the invention advantageously makes an inherently colorless anti-creaking agent visible under the influence of UV light.

[0030] Accordingly, the complete and even application of the anti-squeak agent to the foam element can be controlled, thus ensuring the noise-reducing effect of the anti-squeak agent.

[0031] The method according to the invention makes it possible to avoid the use of colored or dyed anti-creaking agents to control the application of the anti-creaking agent.

[0032] Accordingly, soiling or unwanted staining otherwise associated with the application of the anti-squeak agent advantageously does not occur, as will be made clear by the following description.

[0033] In particular, the invention achieves that the problem of soiling of the seat covers, which otherwise occurs with colored anti-creak agents, is advantageously avoided when the foam elements are covered with a cover.

[0034] By means of the colorless anti-squeak agent according to the invention mixed with fluorescent pigments, the application of the anti-squeak agent on the foam element is made visible or visible, whereby, as explained below, it is advantageously possible to prove that the anti-squeak agent has been applied in the desired manner, and indeed without the seat covers becoming dirty.

[0035] This advantageously allows for monitoring the complete and even application of the anti-squeak agent, for example, when applied by a worker by spraying it on manually. Accordingly, colorless anti-squeak agents can be advantageously used, which are visually imperceptible without the fluorescent pigments or, according to the invention, can only be made visible by the fluorescent pigments in the fluorescent anti-squeak agent.

[0036] Further preferred embodiments of the invention result from the remaining features mentioned in the subclaims.

[0037] According to an advantageous embodiment of the invention, it is provided that the steps of applying the fluorescent anti-creaking agent, irradiating the foam element with UV light and evaluating the light emissions emanating from the foam element, which are visible due to the UV light irradiation, are carried out successively and simultaneously.

[0038] In particular, the UV light irradiation provided during the application of the anti-creaking agent enables the instantaneous distribution of the anti-creaking agent during treatment, thus advantageously enabling control of the even application of the fluorescent anti-creaking agent during simultaneous UV light irradiation, particularly during manual or automated application, for example, using a spray gun. In another approach, the UV light irradiation is performed after the application of the fluorescent anti-creaking agent, particularly for subsequent quality control.

[0039] In summary, it is preferred that the steps of application, irradiation, detection and evaluation take place sequentially or simultaneously.

[0040] Furthermore, it is preferably provided that the application of the fluorescent anti-creaking agent and / or the irradiation of the foam element with ultraviolet light and / or the detection and evaluation of the emitted fluorescent radiation is carried out manually or automatically.

[0041] Furthermore, it is preferably provided that the detection and evaluation of the light emissions emanating from the fluorescent pigments of the foam element is carried out automatically by irradiating the foam element visually by a person or by means of a camera system connected to an evaluation unit.

[0042] The automation of the entire process advantageously enables rapid anti-squeaking treatment with high and consistent quality in an automated production chain, as it advantageously makes it possible to check the correct application of the fluorescent anti-squeaking agent at any time by means of UV light irradiation.

[0043] In other words, a further advantageous embodiment provides for the evaluation of the light emanating from the foam element to be carried out by means of a camera system connected to an evaluation unit or by visual monitoring. The camera system coupled to the evaluation unit can advantageously be used, in particular, to monitor the automated application of the fluorescent anti-squeak agent. Visual monitoring by the worker applying the fluorescent anti-squeak agent advantageously enables control during the treatment process with the fluorescent anti-squeak agent.

[0044] According to an advantageous embodiment of the invention, the fluorescent anti-squeak agent is applied to the foam element by spraying, rolling, brushing, or soaking the foam element. In one embodiment, during the shaping of the foam element, applying the fluorescent anti-squeak agent to the negative mold of the foam element provided for the production of the foam element ensures that the fluorescent anti-squeak agent reaches the surface of the foam element.

[0045] In a preferred embodiment, the anti-squeak agent is sprayed manually or automatically. Especially when spraying manually using a spray gun, the even application can be advantageously controlled, as described, by UV light irradiation and visualization of the fluorescent pigments.

[0046] According to an advantageous embodiment of the invention, it is provided that the fluorescent pigments added to the conventional, in particular colorless, anti-scratch agent are added by adding the marking substance, in particular by adding fluorescein (also referred to as uranine).

[0047] For example, at least 10 g to 50 g of powdered fluorescein are directly added to 1000 liters of anti-squeaking agent as a marking substance, so that fluorescent anti-squeaking agent is available in this way.

[0048] However, it is also possible for the marking substance to be available not in powder form, but as a ready-to-use emulsion consisting of the marking substance and a fluid. Such a luminescent dye emulsion, like powdered fluorescein, is characterized by its bright fluorescence properties. In this case, for example, 1000 liters of anti-squeaking agent, i.e., preferably colorless lubricant, are indirectly added with at least 100 ml to 500 ml of the ready-to-use emulsion as the marking substance. Indirectly, in this context, means that the fluorescent pigments are already premixed with a fluid in the emulsion before it is added to the anti-squeaking agent. This emulsion then contains, for example, 100 ml / 10 g of powdered fluorescein or 500 ml / 50 g.

[0049] It is clear that the skilled person is able to produce the fluorescent anti-creaking agent according to his needs, so that other mixing ratios can also be chosen, as will be explained further below.

[0050] With regard to the mixing ratio between anti-squeak agent and marking substance, the user will add a smaller or larger proportion of the marking substance, as previously explained, in a direct (powder) or indirect (emulsion) manner, according to his needs, in order to produce the fluorescent anti-squeak agent and prepare it for the intended process - application to the foam element.

[0051] It is essential that the user, when capturing and evaluating the fluorescent radiation generated by irradiation with ultraviolet light, which is emitted by the coated foam element after use, i.e. after application to the foam element, is able to preferably a) visually perceive / recognize the generated fluorescent radiation without further aids by the human eye or preferably b) detect it with the aid of aids, in particular a camera or the like.

[0052] The ready-to-use, colorless emulsion is free of suspended matter and formaldehyde and exhibits particularly bright UV excitability. Due to its extremely small particle size, it is characterized not only by particularly good capillary permeability but also by a very intense blue fluorescence under UV excitation, i.e., UV light irradiation, which enables time-saving UV examination of large areas. In this respect, this marking substance achieves a synergy in that it has good capillary permeability, which promotes and improves the application and penetration of the fluorescent anti-squeak agent. At the same time, the synergistic effect enables easy detection through the intense blue fluorescence of the fluorescent anti-squeak agent, which consists of the conventional lubricant and the ready-to-use, colorless fluorescein emulsion.

[0053] The anti-squeak agent, which contains fluorescein, makes the application of the anti-squeak agent to the foam element visible and thus detectable. This advantageously allows for the complete and even application of the anti-squeak agent, especially during manual spraying. Accordingly, otherwise colorless anti-squeak agents can be used advantageously, as they would be visually imperceptible without the fluorescein.

[0054] The use of fluorescein as a marking substance, when used as intended, is environmentally and health-safe. Furthermore, the fluorescent pigments in the marking substance degrade within a few days in daylight, so no adverse long-term side effects are to be expected even when the foam element coated with the fluorescent anti-squeak agent is subsequently used.

[0055] According to an advantageous embodiment of the invention, the fluorescein is dissolved in water prior to use. This advantageously allows for the effective and cost-effective use of fluorescein in strong fluorescence.

[0056] The invention further provides an anti-creaking agent for treating foam elements, which comprises a lubricant, wherein the lubricant acts as the actual anti-creaking agent and fluorescent pigments are added to the lubricant.

[0057] The foam element according to the invention is characterized in that a surface of the foam element is coated with the fluorescent anti-creaking agent.

[0058] The foam element according to the invention prevents noises that would otherwise occur during the relative movement of the foam element and, for example, the cover. Noise prevention is particularly effective because the described method ensures complete treatment of the foam element with the anti-creaking agent.

[0059] Furthermore, the use of fluorescein as a marking substance for producing a fluorescent anti-creak agent comprising a lubricant and the fluorescent marking substance is taught. The fluorescent anti-creak agent is applied to a surface of the foam element and the application of the agent to the surface of the foam element is detected. Detection is performed by irradiating the foam element with ultraviolet light, causing the fluorescent marking substance to emit visible fluorescence radiation, and the application of the fluorescent anti-creak agent to the surface of the foam element is detectable with the naked eye.

[0060] The method for detecting an anti-creak treatment of a foam element of a vehicle seat with the fluorescent anti-creak agent is described in detail below in an embodiment.

[0061] The treatment of the foam element with the fluorescent anti-squeak agent described here is carried out manually using a spray gun.

[0062] First, a provided foam element, in the selected design variant a seat foam element of a vehicle seat, is positioned on a work surface.

[0063] Then the fluorescent anti-squeak agent, which consists of a colorless lubricant and the marking substance fluorescein, is applied to the foam element.

[0064] If necessary, the fluorescent anti-creaking agent is mixed with another liquid before use and only then added to the colorless lubricant.

[0065] In a preferred preparation method, for example, 1000 liters of conventional anti-creaking agent are mixed with 1 to 20 g of powdered fluorescein, so that the fluorescent anti-creaking agent is available for use or application.

[0066] The marking substance, thoroughly mixed with the anti-squeak agent, is applied to the foam element using a spray gun. A UV light source, for example, is directed at the foam element.

[0067] For example, even during application, the sections of the foam element already treated with the fluorescent anti-squeak agent glow due to the fluorescent effect of the fluorescent pigments triggered by the UV light, so that the person / worker applying the anti-squeak agent with the spray gun can visually check that the foam element has been completely and evenly treated with the anti-squeak agent and can therefore carry out the treatment as intended, in the desired quality that corresponds to an even application.

[0068] During automated treatment of the foam element with the fluorescent anti-creaking agent according to the invention, it is advantageously possible to qualitatively record the treatment of the foam element with the fluorescent anti-creaking agent upon exposure to UV light using the UV light source and a camera system connected to an evaluation unit. According to quality control, it is advantageously easy to determine whether a foam element that does not meet the quality criteria needs to be subjected to post-treatment with the fluorescent anti-creaking agent.

Claims

[1] Method for detecting a treatment of a foam element with an anti-creaking agent, comprising the steps of • Providing the foam element; • Providing a fluorescent anti-creaking agent comprising a lubricant used as an anti-creaking agent and a fluorescent marker substance, wherein the fluorescent marker substance is fluorescein, wherein the marker substance emits visible fluorescent radiation upon irradiation with ultraviolet light, • Applying the fluorescent anti-squeak agent to the foam element, • Irradiating the foam element on which the fluorescent anti-squeak agent is applied with ultraviolet light, • Detection and evaluation of the fluorescent radiation emitted by the coated foam element by irradiation with ultraviolet light. [2] Method according to claim 1, characterized bythat the steps of application, irradiation, detection and evaluation take place sequentially or simultaneously. [3] Method according to at least one of claims 1 or 2, characterized by that the application of the fluorescent anti-squeaking agent and / or the irradiation of the foam element with ultraviolet light and / or the detection and evaluation of the emitted fluorescent radiation is carried out manually or automatically. [4] Method according to at least one of claims 1 to 3, characterized by that the detection and evaluation of the emitted fluorescent radiation by irradiating the foam element is carried out automatically, visually by a person or by means of a camera system connected to an evaluation unit. [5] Method according to at least one of claims 1 to 4, characterized bythat the fluorescent anti-squeak agent is applied to the foam element by spraying, rolling, brushing, impregnating or, when shaping the foam element, by applying the fluorescent anti-squeak agent to the negative mold of the foam element intended for the production of the foam element. [6] Method according to at least one of claims 1 to 5, characterized by that the provision of the fluorescent anti-creaking agent is carried out by adding the marking substance to the anti-creaking agent directly in a powdered state or to the anti-creaking agent indirectly in a liquid state, in each case in a predetermined quantitative ratio, wherein the powdered marking substance, in the case of indirect addition, is mixed with a liquid to form an emulsion, which is added to the anti-creaking agent in the predetermined quantitative ratio. [7] Use of fluorescein as a marking substance for producing a fluorescent anti-creak agent comprising a lubricant and the fluorescent marking substance, wherein the fluorescent anti-creak agent is used to apply it to a surface of a foam element, wherein detection of the application to the surface of the foam element is provided by irradiating the foam element with ultraviolet light, whereby the fluorescent marking substance emits a visible fluorescent radiation and detection of the application of the fluorescent anti-creak agent to the surface of the foam element is detectable.