Patent Application
20050136756
1. Field of the Invention
The present invention relates to a laminated article and method for forming the laminated article. More particularly, the present invention relates to a laminated article formed by extruding a polyethylene film and applying a layer of chopped fiberglass or a layer of fiberglass mat to the film while the film is in at least a partially molten state.
2. Description of the Related Art
The interior of a motor vehicle is constantly being improved upon by maximizing the strength and minimizing the weight and cost associated with each component incorporated therein.
One component in the interior of a motor vehicle that is undergoing a transformation is the headliner. The headliner is a large lining that extends over the top of the passenger compartment of the motor vehicle to cover the roof thereof. Typically, the headliner includes a chopped fiberglass laminate formed by feeding a continuous non-woven scrim of fiber material and a non-porous barrier film through a pair of nip rollers. Chopped fiberglass and adhesive are deposited on the moving barrier film and non-woven scrim that is then heated in an oven, passed through pressure nip rollers, cooled and then wound in roll form for transport and use.
A headliner composite may be formed by combining the fiberglass laminate with a foam layer on the fiberglass surface, and additional fiberglass layer is disposed on the opposite surface of the foam and a decorative fabric that may include a foam backing is placed on the exposed fiberglass surface. The headliner composite is then ready for molding. Unfortunately, many time-consuming and costly steps are involved in such conventional manufacturing processes.
The inventor of the present invention has recognized these and other problem associated with conventional processes for the manufacture of a laminated article, such as a headliner, and has developed a laminated article and a method of manufacturing the laminated article that is less time-consuming and less costly. In one embodiment of the invention, a laminated article comprises a layer of film material and a layer of chopped fiberglass deposited on the layer of film material while at least a portion of the layer of film material is in a molten state. In an alternate embodiment, the laminated article comprises a layer of film material and a layer of fiberglass mat applied to the layer of film material while at least a portion of the layer of film material is in a molten state.
A method of manufacturing the laminated article is also disclosed. In one method of the invention, the method comprises the steps of:
In an alternate method of the invention, the method comprises the steps of:
The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
Referring to
The scrim material 12 may be, for example, a nonwoven scrim material formed of a spunbond polyester fiber and has a weight between about 0.50-1.75 oz/yd (17-60 g/m). Preferably, the scrim material 12 has a weight between about 0.8-1.2 oz/yd (27-41 g/m) and is 100% polyethylene terephthalate (generally referred to as polyester or PET) fiber. In the exemplary embodiment, the scrim material 12 is a 100% polyester spunbond fiber weighing 1.00 oz/yd (34 g/m).
The barrier film 14 is formed of a thermoplastic film that may be formed of one or more layers. There are a wide variety of such barrier films available which are suitable for use in laminated article 10. A particular film chosen will depend on the headliner manufacturer's tool and the molding conditions, such as tool temperature and dwell time. The barrier film 14 may be a polyolefin film or may be a blend chemistry and can be formed of a single or multilayer structure. As noted, a wide selection of barrier films is suitable. Specific examples include Dow Integral 925 film that is a tri-layer film having a core layer heat stable up to about 165° C. (330° F.) and having outer polyethylene adhesive layers that are heat activated at temperatures of about 127° C. (260° F.).
The fiberglass layer 16 is formed by depositing chopped fiberglass on the exposed surface of the barrier film 14. The fiberglass applied to barrier film 14 is chopped to provide a range of between about 30-200 g/m of fiberglass with strands having a length between 1.0 and 4.0 inches. Preferably, the length of the chopped rovings is about 2.0 inches. Chopped glass fibers are applied to the barrier film 14 in a random fashion and may be combined with an anti-static chemical sizing agent to reduce static buildup at the glass chopper.
While the barrier film 14 is still in the molten state, the barrier film 14 is fed below a fiberglass chopper dispenser 26 where chopped fiberglass in the desired quantity is deposited on the exposed surface of the barrier film 14 to form a fiberglass/barrier film/scrim composite 28. Preferably, the deposition of the chopped fiberglass onto the exposed surface occurs at a distance of a few inches to a few feet from the extruder 24. It will be appreciated that the scrim material 12 and the chopped fiberglass layer 16 can be applied to the barrier film 14 at approximately the same time, rather than in subsequent steps, to ensure that the barrier film 14 is still in the molten state. Because the adhesive layers of the barrier film 14 are activated when the scrim material 12 and the chopped fiberglass layer 16 are applied, the requirement to heat the composite 28 in an oven, for example, to activate the adhesive layers is eliminated.
The composite 28 is laminated at a nip roller 30 to form the laminated article 10. The nip roller 30 is maintained at a temperature just below room temperature and applies a downward pressure of between about 10-80 lbs/in to the composite 28. Preferably, between about 30-40 lbs/in pressure is applied, and most preferably about 20 lbs/into form the laminated article 10. The actual pressure depends on the amount of fiberglass added at the fiberglass chopper 26 and the thickness deposited on the barrier film 14.
The laminated article 10 may then be further cooled at one or more cooling rollers 32 that are maintained below room temperature. The cooling rollers 32 further cool the laminated article 10 and provide a desired amount of tension between the cooling rollers 32 and a final batch roller 34 where the laminated article 10 is wound.
Referring now to
While the barrier film 14 is still in the molten state, the barrier film 14 is fed below a fiberglass mat dispenser 26′ where the fiberglass mat 16′ is applied to the exposed surface of the barrier film 14 to form a fiberglass/barrier film/scrim composite 28′. Preferably, the application of the fiberglass mat 16′ to the exposed surface occurs at a distance of a few inches to a few feet from the extruder 24. It will be appreciated that the scrim material 12 and the fiberglass mat 16′ can be applied to the barrier film 14 at approximately the same time, rather than in subsequent steps, to ensure that the barrier film 14 is still in the molten state. Because the adhesive layers of the barrier film 14 are activated when the scrim material 12 and the fiberglass mat 16′ are applied, the requirement to heat the composite 28′ in an oven, for example, to activate the adhesive layers is eliminated.
The composite 28′ is laminated at the nip roller 30 to form the laminated article 10′. The laminated article 10′ may then be further cooled at one or more cooling rollers 32 that are maintained below room temperature. The laminated article 10′ is wound at the final batch roller 34.
As mentioned above, the laminated article 10, 10′ may be used in a headliner of a vehicle. Referring now to
The laminated article 10, 10′ manufactured in accordance with the process illustrated in
Some laminated articles require the use of a thermoset resin to bind together the various layers of the headliner assembly. As a result, the composite forming the laminated article must be heated in order for the resin to properly bind the layers of the laminated article. Additionally, conventional laminated articles require an additional step of pre-mixing the thermoset resin with a catalyst before applying the mixture to the composite. By applying the optional scrim material and the chopped fiberglass/fiberglass mat while at least a portion of the barrier film is in a molten state, the method of the invention eliminates such steps, thereby reducing the time and cost of manufacturing the laminated article.
It should be noted that while the present invention is directed towards a headliner assembly, the present invention may be applied to various components within the vehicle, including, for example, a door trim, or a luggage trim, or the like.
While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit.
