CN115742906A - Interior trim component with reduced odor and VOC - Google Patents

Abstract

A molded automotive interior trim component comprising at least a pile carpet dedicated to facing the passenger compartment. It further comprises an odor-absorbing layer comprising at least a first adhesive layer, a first activated carbon layer, a second adhesive layer and a second activated carbon layer, a third adhesive layer and a meltblown nonwoven cover layer, wherein the first adhesive layer is applied and attached directly to the napped carpet surface facing away from the passenger compartment.

Description

Interior trim component with reduced odor and VOC

Technical Field

The present application relates to interior trim components, in particular carpet flooring systems, floor mats or dash panels, which reduce odor and/or VOC's in the passenger compartment.

Background

Vehicle occupants are aware that interior trim components release Volatile Organic Compounds (VOCs) for a period of time immediately after production of new vehicles, especially when they develop a so-called "new car odor". The release may last a long time and may be accelerated by the vehicle being parked in an environment with an elevated temperature, such as in the sun or in a warm climate.

In addition, new odors may enter the passenger compartment during vehicle use.

Legislation and new awareness of vehicle users has increased the need for powerful systems to reduce or eliminate VOCs in the materials used, as well as any released VOCs and odors in the enclosed environment of the vehicle passenger compartment.

VOCs, particularly formaldehyde and acetaldehyde, may be released by different materials used for interior trim parts. Known sources are foams, including slabstock and direct foam layers, and virgin polyester used in the fiber layers. In addition, a glue layer or release agent may increase the overall level of VOC released in the passenger compartment.

While scavengers and adsorbents are available to capture VOCs, once they are used in the material they are either embedded in the binder or resin solution used, or are not used in powder form and may fall off or in the worst case pose a hazard themselves.

In addition, most scavengers preferentially react with one aldehyde and may even release one aldehyde first and thus give way to another aldehyde. This balance may be disturbed or changed depending on environmental conditions such as temperature changes. This is something that may happen in vehicles that are parked and used under climatic conditions.

It is therefore an object of the present invention to provide an interior trim part, in particular a carpet flooring system, a floor mat or a front wall panel, for reducing odours and/or VOCs in the passenger compartment, which does not have the problems of the solutions of the prior art and in particular can remain active for a long time.

Disclosure of Invention

This object is achieved by a molded automotive interior trim component according to claim 1, comprising a pile carpeted surface, dedicated to face at least the passenger compartment.

In particular, by incorporating an odor absorbing layer comprising at least a first glue layer, a first activated carbon layer, a second glue layer and a second activated carbon layer, a third glue layer and a meltblown nonwoven cover layer, wherein the first glue layer is applied and attached directly to the napped carpet surface facing away from the passenger compartment, a lightweight thin VOC and odor absorbing layer can be created. Surprisingly, the amount of gum and activated carbon used is minimal; preferably, the surface is not completely covered. The process of the present application, in combination with a small amount of gum and activated carbon, forms a layer that can exhibit its full capacity in capturing VOCs at higher levels than desired. It does not appear to embed completely into the glue layer leaving more space to accommodate the activated carbon and optional scavenger loaded onto the activated carbon.

Surprisingly, the functionality of the activated carbon and optional scavenger is maintained even after thermoforming the trim piece.

Preferably, the adhesive layer is a pressure sensitive adhesive based on at least a polyolefin, preferably one of polypropylene or polyethylene. The glue layer is intended to be more adhesive than the layer surrounding the activated carbon particles.

All glue layers are added together to 20-50gsm, preferably 25-35gsm. The glue layer can be finely dispersed on the back of the fluff layer by using a spray gun type sprayer, but other application systems that produce a fine layer can also be used.

Preferably the activated carbon in all layers together is 120-250gsm, the actual amount of activated carbon being so low that the particles may not cover the whole surface. Preferably, a naturally based, e.g., coconut based, carbon may be used. The preferred particle size range is 200-800 μm.

Preferably, the activated carbon used is loaded with an aldehyde scavenger, preferably at least one of polyacrylamide, ethylene urea and carbohydrazide.

Preferably, the scavenger used is at least 0.5% by weight of the activated carbon, preferably at most 1.5% by weight of the activated carbon.

The molded automotive trim part may further comprise at least one backing layer selected from the group consisting of a polyurethane foam layer laminated and bonded to the meltblown layer, a thermoplastic and/or natural felt layer, a nonwoven layer, a fluff layer, a thermoplastic resin layer, and a foil layer.

The pile surface may be a tufted carpet system or a nonwoven carpet system as known in the art.

Preferably, the glue and activated carbon are repeatedly applied to better cover the back of the nonwoven trim. It was found that at least two layers of alternating gums and activated carbon, wherein the amount of gums and activated carbon is just sufficient to cover the surface with a thin layer, which is more effective than using a thick layer of gum embedding activated carbon into what is commonly used.

Preferably, glue is sprayed on the back of the top layer, e.g. on a needle-punched non-woven carpet, to obtain a "wetting" of the surface. Since the back surface is fibrous and therefore not a flat surface for sizing, the spray system, rather than the extrusion system, has the advantage of covering the entire surface and maintaining the surface topography of the fibrous layer, so the activated carbon will also adhere to the fibrous surface at a level different from the flat surface. By applying a second round of fine glue sprayed layer and activated carbon, the carbon of the first round may not be completely covered, thereby maintaining its function.

Surprisingly, this way of applying activated carbon directly to the back of the surface layer covered with a non-woven fleece or scrim (script) retains functionality even after the part is molded.

In order to further optimize the reduction of aldehyde emissions of the molded trim part according to the invention, the final molded part may be subjected to additional treatments at least on a part of its outer surface. The outer surface may be covered with a network of amino-silane and/or amino-siloxane molecules that partially hydrogen bond to adjacent surfaces to further reduce aldehyde emissions.

Surprisingly, very small amounts of aminosilane are required to achieve the desired results. Preferably, the amino-silane used is at least 0.02% and no more than 0.1% by weight of the part.

The aminosilane or aminosiloxane is preferably one of the group of silane compounds having an amino group or a diamino group and at least one alkoxy group.

Preferably, the aminosilane is at least one of the group of NH 2-siloxysilanes, for example at least one member selected from the group consisting of: -N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (aminoethylaminomethyl) phenyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltris (2-ethylhexyloxy) -silane, aminoethyl-aminopropyl-trimethoxysilane, 3- (dimethoxymethylsilyl) propylamine, -N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, trimethoxysilylpropyldiethylenetriamine, bis (2-hydroxyethyl) -3-aminopropyltrimethoxysilane and the like.

Surprisingly, by combining the activated carbon layer with the surface treatment, it is possible to reduce the initial emissions of new components newly installed on the automobile, as well as to reduce the long-term emissions and odors during long-term use of the vehicle.

Drawings

Figure 1 shows a schematic view of a preferred layering of a trim part 5 according to the invention.

The trim part comprises at least a pile surface layer 1, which may be a tufted carpet system or a needle-punched carpet system, both known in the art, which pile surface forms a surface layer that can be seen and/or touched by a passenger when placed in a vehicle, for example as an aesthetic covering of a floor or as a floor mat.

On the surface of the pile surface layer dedicated to the back facing the passenger compartment, a first layer of glue 3 of 10-25gsm is preferably sprayed. Preferably, a polyolefin-based glue is used, such as a polypropylene or polyethylene-based glue. Immediately after sizing, a first layer of activated carbon 4 is sprinkled on top of the freshly applied glue, as long as the glue is still at least sticky. The first round of application is indicated in the picture with a. The activated carbon is applied at an areal weight of 70-100gsm per layer.

After the first application, a second application round B is directly performed, wherein again first the glue layer 3 'and the activated carbon layer 4' are used in the same or similar amounts as in the first round. Although different concentrations may be used between the layers of the first and second round, this has no benefit to the overall result. The amount used per round depends on the surface structure of the pile layer. Additional runs of glue and activated carbon may be applied depending on the part and need, although in most cases 2 runs are already sufficient to significantly reduce aldehydes, TVOC and odor when used in an automobile. The final glue layer 3 "is applied to join to the meltblown nonwoven layer.

Preferably, a polypropylene (PP) meltblown nonwoven fabric with a fiber diameter of 1-5 microns is used. The meltblown fabric preferably has an areal weight of 10-25gsm, more preferably about 15-20 gsm. The meltblown layer may be melted and laminated to any layer used adjacent to the layer.

Surprisingly, the glue type, application form and melting of the meltblown layer do not have a negative impact on the efficacy of the activated carbon as the standard glue layers of the prior art do; in particular a powder glue layer or an extruded glue layer which seems to have a negative influence on the efficacy of the odour-absorbing layer.

The combination of alternating layers of glue and activated carbon together with the meltblown layer forms the odour-absorbing layer 7.

Surprisingly, the meltblown layer was adhered to the last round of gum-activated carbon to cover and protect the odor absorbing layer during storage and transportation. This layer also facilitates lamination to any other layer on the back of the carpet system (6).

The backing layer 6 is drawn as a black box in the drawing because it may be at least one layer or a combination of layers.

For example, to form a floor mat, a combination of a low density polyethylene layer, a film layer, a second low density polyethylene layer may be used. The carpet system is made into a floor mat by thermoforming and laminating one or more backing layers (6) to the lower surface of the meltblown layer, thereby at least partially melting the layer.

Another option is to form an automotive molded flooring component wherein the backing layer may be at least one of an EPDM layer, a TPA layer, a felt layer, a foam layer, a film layer, or a combination of these layers.

Examples

Total VOC emissions (TVOC) were measured in new vehicles fully equipped with a common set of trim parts and panels until equilibrium was reached. This is a baseline TVOC emission level, which is high for a new vehicle parked for several days with the doors and windows closed. A floor element in the form of a mat according to the invention comprising activated carbon loaded with an acetaldehyde scavenger, such as polyacrylamide, is placed in a car. The TVOC was measured again for several days until equilibrium was reached. It can be shown that the flooring component comprising activated carbon according to the present invention is capable of reducing TVOC by more than 30% while a significant reduction of acetaldehyde emissions by more than 40% is also observed. And surprisingly, a slight reduction in formaldehyde was observed, although the scavenger used was more specific to acetaldehyde.

Interestingly, by removing the floor component from the passenger compartment, an additional reduction in TVOC can be observed, which may be associated with any random absorption of VOC components and binding to surfaces, which are thus also removed from the passenger compartment.

In addition to the TVOC, the odor was tested using pieces of the same carpet stored in Tedlar bags and heat treated to remove any odor on the parts. The parts were tested according to odor test method PES11082 (GM custom standard) using a manually trained test panel.

Although carpet constructions without an odour-reducing layer according to the invention only reach 5-6 in the range of 1-10, which corresponds to a critically tolerable, carpet comprising an odour-reducing layer according to the invention reaches 7a, i.e. a noticeable but not objectionable odour. Therefore, the odor test results were increased by nearly 2 levels, bringing them into acceptable ranges.

Claims (12)

1. A molded automotive interior trim component comprising a pile carpet facing at least specifically toward the passenger compartment, characterized by further comprising an odor-absorbing layer comprising at least a first glue layer, a first activated carbon layer, a second glue layer and a second activated carbon layer, a third glue layer and a meltblown nonwoven cover layer, wherein the first glue layer is applied directly to and attached to the pile carpet surface facing away from the passenger compartment.

2. The molded automotive trim component of claim 1, wherein the adhesive layer is a pressure sensitive adhesive, preferably in combination with at least one polyolefin-based adhesive, preferably one of polypropylene-based or polyethylene-based adhesives.

3. The molded automotive trim component of one of the preceding claims, wherein all glue layers add up to 20-50gsm, preferably 25-35gsm.

4. The molded automotive trim component of one of the preceding claims, wherein all activated carbon is 120-250gsm.

5. The molded automotive trim component of one of the preceding claims, further comprising at least one backing layer selected from the group consisting of a polyurethane foam layer, a thermoplastic and/or natural felt layer, a nonwoven layer, a fluff layer, a thermoplastic resin layer, and a foil layer laminated and attached to the meltblown layer.

6. The molded automotive trim part of one of the preceding claims, wherein the pile carpet can be a tufted carpet system or a nonwoven carpet system.

7. The molded automotive trim part of any one of the preceding claims, wherein the activated carbon is loaded with an aldehyde scavenger, preferably at least one of polyacrylamide, ethylene urea and carbohydrazide.

8. The molded automotive trim component of one of the preceding claims, wherein the scavenger is at least 0.5% by weight of activated carbon, preferably at most 1.5% by weight of activated carbon.

9. The molded automotive trim component of one of the preceding claims, wherein the molded trim component is covered, at least on a portion of its outer surface, with a network of amino-silane and/or amino-siloxane molecules that are partially hydrogen bonded to an adjacent surface.

10. The molded automotive trim part of claim 6, wherein the aminosilane or aminosiloxane is one of the group of silane compounds having an amino group or a diamino group and at least one alkoxy group.

11. The molded automotive trim component of claim 6, wherein the amino-silane is at least 0.02% and no more than 0.1% of component weight.

12. The molded automotive trim component of one of claims 5, 6, or 7, wherein the aminosilane is at least one member selected from the group consisting of: n- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (aminoethylaminomethyl) phenyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltris (2-ethylhexyloxy) -silane, aminoethyl-aminopropyl-trimethoxysilane, 3- (dimethoxymethylsilyl) propylamine, -N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, trimethoxysilylpropyldiethylenetriamine, bis (2-hydroxyethyl) -3-aminopropyltrimethoxysilane and the like.

Images