JPH02261623A - Production of laminated material - Google Patents

Abstract

PURPOSE: To obtain a manufacture of a laminated material which is economic and stable and which requires simple processing by deforming materials to a desired final shape by placing an intermediate laminate product in a heated mold without being preheated as well as by curing an adhesive applied to a reinforcing web. CONSTITUTION: A reinforcing material, preferably a glass fiber matting, feeds a reinforcing web to a dip coating bath 3 containing an adhesive solution, preferably phenol formaldehyde resin 3a. The coated web passes through rollers 4 which squeeze out of the web any excess liquid resin. The web then passes through an oven 5 in which excess water or solvent fluids are dried off to leave a dry pre-coated reinforcing web. The reinforcing material forms an intermediate laminate product 14 by placing a cellular core layer 11 on the web. The intermediate laminate product 14 is thereby carried to a molding station 17 and placed between dies 18, 19 of a mechanical or hydraulically operated double-acting press. The dies are electrically heated to a temperature sufficient to mold the thermoformable cellular core and to cure the adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a reinforcing web for a laminate, a method for manufacturing a laminate, and a laminate. In one embodiment, the present invention relates to a molded laminate that optionally incorporates a porous material.

- Laminated materials with reinforcing and/or decorative layers of:
For example, it is used in the automotive and aircraft industry as ceiling lining panels (so-called "ceiling panels"), door panels, automobile engine compartment insulating panels, and decorative panels for boats. In some cases, the laminate has porous layers.

[Conventional technology]

Such panels can be manufactured by a number of previously proposed methods, for example British patent B-2.
No. 096653 discloses a lightweight, insulating, insulating material consisting of impregnating a flexible connected cell porous material with a solution of an isocyanate compound and crosslinking the isocyanate by reacting the isocyanate with water to form a urea or biuret derivative.
Describes a method for producing flexible rigid or semi-rigid laminates. This impregnation step can be followed or accompanied by the step of depositing the fibrous material onto the porous material and allowing the isocyanate to act as a binding and fixative for the fibers.

Laminated panels containing a thermoformable porous material, such as polyurethane foam, as core material can be produced by heating the thermoforming material to a moldable temperature and then placing this preheated material in a mold. proposed so far. Before the core material is placed in the mold, the sides of the mold are applied with the desired reinforcing and/or decorative layers for the final product, and these layers are coated with a suitable adhesive for bonding to the core material. covered with. The mold is also preheated to a temperature sufficient to set the adhesive but below the thermoforming temperature of the foam core. When the mold is closed, the reinforcing and/or decorative layers bond to the core material and the panel is formed into the desired final form.

Also, in our European Patent Application No. 0266224, we propose a method for producing a laminate containing at least one reinforcing layer and a thermoformable porous core material, without preheating the material before the forming process. The adhesive for bonding the zero layers together to form the intermediate laminate is sprayed onto the reinforcing layer before contacting the core material, thus eliminating the need to impregnate the foam core. The intermediate laminate is then placed in a heated mold that serves both to deform the thermoformable porous core material and to secure the adhesive.

We now provide an improved method of making reinforcing webs for use in laminates, and an improved manufacture of laminates that is economical, stable, and easy to process. In particular, we have found it advantageous to pre-treat the reinforcing web, for example by adding adhesive by impregnation or coating, before it is used in the laminate manufacturing process.

Thus, one aspect of the present invention is to overlay a thermoformable porous core material onto a reinforcing web (which has been pretreated by adding an adhesive to the web) to form an intermediate laminate product. and the intermediate laminate product is placed in a heated mold without substantial preheating to transform the material into the desired final form and to cure the adhesive. A method of making a laminate comprising a core material and at least one pretreated reinforcing web is provided.

According to a preferred embodiment, the method of the invention is used to produce a laminate having a plurality of reinforcing layers, conveniently two or more reinforcing layers. It has a backing or scrim layer with a decorative surface and a top layer depending on the desired use. Thus, in a most preferred embodiment, the method produces a laminate having a scrim or backing layer, a first reinforcing layer, a porous core layer, a second reinforcing layer, and a top surface layer. used to do. In this embodiment, the scrim is conveniently made of e.g. polyester, viscose, glass fiber or combinations thereof, e.g.
-' weight of non-woven or woven fabric. The first reinforcing layer is advantageously an organic or inorganic material selected from carbon, boron, polyamide, polyester, viscose, ceramic, cotton, metal fibers and combinations thereof, and is preferably laid over the scrim. Weight 1F 50-400
gm-", preferably from 100 gm-" to 200 gm-", is comprised of a non-woven material glass fiber mantle. A particularly suitable material for the reinforcing layer consists of a non-woven shredded glass strand mat weighing approximately 150 g+-''. The scrim is generally an open-woven fabric.The scrim may be pre-coated on the back side of the laminate, for example with a polyethylene film, which provides a more comfortable finish and increases the strength of the final product. Additionally, if desired, the reinforcing layer may be impregnated with a suitable resin before being used in the method of the invention.

In the pretreatment operation, the reinforcing web is coated with adhesives, preferably polyurethanes, phenol formaldehyde, polyesters, acrylics, vinyls, epoxies, polyestersulfenes, and mixtures of many others, for later use in the process. The thermosetting resin adhesive is prepared by adding a thermosetting resin adhesive, the physical form of which is a liquid, a thin film, and a powder.

Selection of a particular type of adhesive depends on many factors. Thus, in general, the formulation and properties of the molded laminate are influenced by the adhesive in the following respects.

(a) The adhesive can provide a substrate support element for reinforcement that affects the strength and stiffness of the laminate.

(b) High thermosetting properties are usually required to preserve detail, such as surface detail in molded laminates.

(c) The adhesive is usually selected to achieve adhesion of the reinforcing layers to each other and to the porous ohmic core (when two reinforcing layers are desired).

(d) the adhesive also affects high temperature stiffness;
Therefore, de-molding of laminates
g) It is desirable to achieve stable and dimensionally accurate molding even when immediately removed from the mold, as this affects the properties.

(e) Where applicable, the adhesive should exhibit high temperature thermal stability to withstand degradation under extreme environmental conditions depending on the service specifications and service conditions of the end use or industry concerned.

Adhesives can be conveniently classified into two types.

(a) Adhesives with a short reinforcement environmental life, typified by polyurethane adhesives, which can be added wet to the reinforcing layer and molded before drying.

(b)? Added to the reinforcing layer using the W-type or dry method, it can have a long shelf life before use in the manufacture of laminates, and can be revived by applying heat during use. Adhesive with an environmental lifespan.

A preferred adhesive for use in accordance with the present invention is a phenol formaldehyde resin. The phenol formaldehyde resin is preferably added in liquid form for coating or impregnating the reinforcing mantle at any time prior to molding.

In some cases, the adhesive may suitably include an aqueous or organic solvent-based carrier.

Using the pre-treatment method according to the invention, the adhesive on the reinforcing layer is dried and then the layer is re-rolled into a long reinforcing material;
It is then used in subsequent lamination and molding operations for the production of laminates.

By drying the web, it is possible to create a product that can be stored for an indefinite period of time before subsequent use in the method of the invention, if necessary and/or desired. This is very convenient for the processor and has economic advantages.

The desired dry pick weight is preferably controlled in the range 10-100 g per square meter.
A dipping process is preferably used to coat or impregnate the reinforcing layer in order to obtain an adhesive of up to 100% strength.

The dry pull weight of the resin typically depends on the density of the web and the final properties required for the laminate.

A drying opening is preferably used in the production of the reinforced web to provide a drying means for removing the desiccant or solvent after the addition of the adhesive, thereby resulting in a reinforced web with a dry coating. . The combustible reinforcing web is thereby rendered non-tacky and therefore can be re-rolled into long continuous lengths that can be stored for later use in the forming process to form the laminate, as described above. suitable for

In a later method for producing laminates, the material for the desired laminate layers is fed from a reel stand so as to be fed successively to one or more forming presses.

The molding process does not require preheating of any of the laminating layers, and all materials are passed directly to the molding press as is.

Once the reinforcing layer is manufactured, it is later used in a process to form a laminate, in which a thermoformable porous core material is added. When the laminate product is intended for use where acoustic damping properties are required, such as for decorative panels in automobiles or aircraft, it is preferred to use open-cell core materials. The material of the discontinuous cell is
Can be used for other purposes. Porous materials can be rigid, semi-rigid or flexible depending on the desired end use. For boat fishing, the thermoformable porous material is polyurethane, although other porous materials such as thermoplastic foam materials can be used if desired. For automotive applications, it is desirable to use thermoformable porous materials such as polyurethane, which provide better moldability and results in products such as ceiling coverings.

The core material is preferably cut to size and thickness appropriate for the desired end product before being overlaid on the pretreated reinforcing layer. The core material can conveniently be cut from slab or roll material. The core material can also be preformed into the desired shape.

For ceiling applications, the core material generally has a thickness in the range from 20 to 3 Qmm.

When the core material is overlaid on the first reinforcing layer, second and subsequent reinforcing layers can be overlaid on top of the core material, if desired. The next reinforcing layer is generally the same as the first reinforcing layer, but this is not required.

In the final step to create the intermediate laminate, a top layer, which can optionally be a decorative layer, can be added to the second reinforcing layer. The top layer may be any material that helps provide the desired appearance of the final product, such as woven, nonwoven, and thermoplastic film materials.

Once the top layer is added, the intermediate laminate is transferred to the molding operation without substantial preheating. The molds used correspond to the desired shape of the final product and are preheated to a temperature which causes the intermediate laminate to deform into the desired shape and to cause curing of the adhesive layer. Molding temperatures in the range 100-200°C have been found to be convenient, with 180'''C being preferred. If, for example, a heat-sensitive decorative layer is used, the area in contact with the decorative layer may be A mold that has a low temperature can be used.
It is held in the mold for 80 seconds, preferably 60-90 seconds. The edges of the mold generally sandwich the top and bottom layers of the stacked devices. Other shaped edges can be formed on the final product in a conventional manner to assist in fining the final product and to prevent subsequent glabellar peeling.

After the molding process, the laminated product is generally cooled in a cooling mold to maintain the desired shape and dimensions of the product.

Optionally, the mold may include air vent holes to remove air from the product and facilitate cooling.

In a variation of the above method contemplated as falling within the scope of the present invention, it is possible to produce a laminate similar to that described above, but omitting the thermoformable porous core material. In a preferred embodiment of this modified method,
A laminate is produced having - scrim or backing layers, - or more curing layers, and optionally a top layer which can have a decorative surface if desired.

In a most preferred embodiment of this variant, there is provided a method for producing a laminate having a backing or scrim layer, first and second reinforcing layers and a top layer. The scrim, reinforcement and top layers were prepared by a method quite similar to that described above, with the only exception that the porous core material was omitted.
Laminated together. A laminate according to a particular embodiment may thus have a weight of 2
5-35 g-m-'' of non-woven backing layer and e.g.
Weight approx. 150 g with polyester/viscose
A first reinforcing layer consisting of a glass fiber mat of "-m-" and a second similar reinforcing layer, weighing 80-150 g, m-
The reinforcing layers, which may consist of the top layer of ``, will have been pretreated as described above, i.e. by pre-adding adhesive. and a female mold to produce an intermediate product which is placed under similar conditions as described above.

As mentioned above, the laminates produced according to the invention are particularly suitable for use in the automotive and aircraft industry, for example as decorative panels, such as the ceilings of cars, pans and trucks. The modified laminate products described above that omit the porous core layer may be particularly useful as insulating panels for automotive engine compartments, where the laminates are non-flammable or self-extinguishing. It should be formed using the material or by treating the material with flame retardant chemicals. Examples of non-combustible porous core materials include phenol formaldehyde, which can be used with non-fuel resin adhesives such as phenol formaldehyde resin; polyether sulfone and polyetherimide foams.

Polyvinyl fluoride is an example of a non-flammable material that can be used as a decorative layer.

Embodiments of the invention will now be described by way of non-limiting examples with reference to the accompanying drawings, in which: FIG.

In the apparatus shown in FIG.
f 5tand). The dancer arm 2 feeds the reinforcing web to a dip coating bath 3 containing an adhesive solution, preferably a phenol formaldehyde resin 3a.

The coated web then advances to rubber coated pinch rollers 4 which squeeze excess liquid resin from the web.

The web then proceeds to a heated oven 5 where excess water or solvent liquid is dried so as to result in a pre-coated dry reinforcing web. The web is then stored in a warehouse for use when required. It is conveniently wound again into a roll 6 for easy handling.

In the apparatus shown in FIG.
The reinforcing material is then pretreated, for example using the apparatus shown in FIG. The bonded web thus formed is then fed to an automatic sheet feeder 10 which overlays the porous core layer 11 onto the web. Of course, it is possible to later overlay the porous core layer 11 on top of the web if desired. The porous core layer 11 is manufactured from a slab material by means of equipment (not shown) for cutting sheets of the desired size and thickness.

A second layer of pretreated material is drawn off roller 12 and superimposed on the porous core layer on the web. Decorative facing material is drawn off rollers 13 and added to the substrate to form intermediate laminate 14. The intermediate laminate is then subjected to a single or multiple forming press operation.

A gripper conveyor 15, known as a tenter-type conveyor in FIG. The intermediate laminate is thereby conveyed to the forming station 17 and placed between dies 18, 19 of a mechanically or hydraulically operated double-acting press. The die is electrically heated to a temperature sufficient to form the thermoformable porous core and cure the adhesive. If the decorative layer on the intermediate product is heat sensitive, the temperature of the upper die 18 will be lower than that of the lower die 19.
The temperature may be lower than that of

Once the press dies 18,19 are opened, the laminate is conveyed to a mechanically or hydraulically operated trimming press 20. The trimming press 20 can be provided with cutting dies 2 and 22 for cutting the formed laminate into desired dimensions.

The product can optionally be conveyed to a cooling section which holds the product in another double-acting press. The die of the press is conveniently cooled with cold water.

The final laminate 23 can be conveyed to the release station where the clip 16 is released and the product is removed.

The product allows economical material usage and a simplified molding process line. Furthermore, the need to spray adhesives onto the reinforcing layer during the molding process is eliminated, and in particular the need to spray isocyanate-type adhesives is eliminated, so there is a significant benefit of no health risks. be.

Although the above example uses two reinforcing layers, a core layer, a scrim layer and a decorative layer to form five layers, laminates with more or fewer layers are also contemplated. It will be understood that it is within the scope of the invention.

It will be appreciated that the modified product described above, i.e. omitting the porous core layer, can also be manufactured with an apparatus similar to that shown in the drawings, omitting only the sheet feeder IO.

[Brief explanation of drawings]

FIG. 1 is a schematic side view of an apparatus for use according to one embodiment of the invention in the production of reinforcing layers. FIG. 2 is a schematic side view of an apparatus for use according to an embodiment of the invention in the production of automotive ceiling coverings. ■, 7゜2 ・ ・ ・ 3 ・ ・ 3a ・ ・ 5 ・ ・ 6 ・ ・ ・ 9 ・ ・ 8.12.13...Roller, dancer arm, dip coating tank, ・Phenol formaldehyde resin , oven, roll, pinching roller, lO・l1・14・l5・16・l7・18゜20・21゜23 ・・・・Automatic sheet feeder, ・・porous core layer, ・・intermediate Laminate, ...Gripping conveyor, ...Clip, ...Forming section, 19.Dice mold, ...Trimming press, 22.Dice mold for cutting, ...Final laminate. Patent applicant: John Kotton (Korun) Ltd. Patent attorney: Morisanbe Suzuki

Claims (21)

[Claims] (1) Layering a thermoformable porous core material onto a reinforcing web (which has been pretreated by adding an adhesive to the web) to form an intermediate laminate product; a thermoformable porous core material and at least one pre-treated material, characterized in that it is placed in a heated mold without preheating to transform the material into the desired final form and to cure the adhesive; A method for producing a laminated material consisting of a reinforcing web. (2) The manufacturing method according to claim 1, wherein the adhesive is a thermosetting resin. (3) The adhesive is polyurethane, phenol formaldehyde, polyester, acrylic resin, vinyl,
3. Process according to claim 2, characterized in that it is an epoxy, a polyester sulfene or a mixture thereof. (4) The manufacturing method according to claim 3, wherein the adhesive is a phenol formaldehyde resin. (5) the adhesive is added to the reinforcing web by dipping the reinforcing web in adhesive;
The manufacturing method according to any one of claims 1 to 4. (6) the adhesive is applied to the reinforcing web in liquid form, and the adhesive is dried after being applied to the web and before the thermoformable porous core material is overlaid on the web; The manufacturing method according to any one of claims 1 to 5, characterized by: (7) The method according to claim 6, characterized in that the adhesive is dried in a drying oven. (8) The manufacturing method according to any one of claims 1 to 7, wherein the adhesive contains an aqueous or organic solvent carrier. (9) The water or organic solvent is removed from the adhesive after being added to the web and before the thermoformable porous core material is overlaid onto the web. Manufacturing method. (10) The method according to claim 9, characterized in that water or organic solvent is removed by a drying oven. (11) Process according to any of the preceding claims, characterized in that the web is coated or impregnated with an adhesive. (12) Any of the preceding claims characterized in that the laminate consists of a scrim layer, a first reinforcing layer, a porous core layer, a second reinforcing layer and a top decorative web layer. Manufacturing method described. 13. The method of claim 12, wherein the first and second reinforcing layers are substantially the same. 14. Process according to any of the preceding claims, characterized in that the core material is cut to a size and thickness suitable for the desired end product before being laid up into a web. (15) A laminate manufactured using the manufacturing method according to any one of the above claims. (16) A laminate according to claim 15 in the form of an automobile ceiling. (17) A laminate according to claim 15, wherein the porous core is omitted. (18) A laminate according to claim 17 in the form of an insulating panel for the engine compartment of a motor vehicle. (19) Adding a liquid adhesive to the reinforcing web and drying the adhesive after adding to the web and before using the web in the laminate.
18. A method for producing a reinforcing web for use in a laminate according to any of 18. (20) The method according to claim 19, characterized in that the adhesive is dried in a drying oven. (21) A reinforcing web for use in a laminate manufactured using the manufacturing method of claim 19 or 20.