IE970351A1 - A process for the treatment and manufacture of furniture and¹furnishings - Google Patents

Abstract

A process for the manufacture of furniture comprising cutting raw material into required shapes, assembling the shapes into an item, applying a base coat to the item, applying a finishing coat to the furniture item before the base coat is dry and mixing the base coat and finishing coat in situ on the item of furniture.

Description

The invention relates to a process for the treatment and manufacture of furniture and furnishings hereinafter referred to collectively as furniture. 0, § ft OO In the manufacture of furniture and furnishings it is frequently desirable to produce a finished item having a unique finish to render the items or range of items distinctive. A particularly preferred form of finish is a distressed or marbled finish in which new raw materials used in the manufacture of the furniture is treated to imbue the item with a reproducible distressed or aged appearance.

However, the various items in a range can be formed from different raw materials such as timber, metal etc.

Accordingly, difficulties arise in arriving at a reproducibly similar or identical finish within a range * of 'items when said items are produced from different raw materials .

In addition, in the application of paint materials to furniture items it is frequently necessary to have significant drying times between application of various coats which can delay the manufacturing process. • 1 Ιλ·> <Λ An object of the invention is to provide a process for the manufacture of furniture in which a reproducibly consistent finish to the product is achieved.

A further object of the invention is to provide a 5 process for the production of furniture in which a similar or identical finish is achieved with metal and timber raw materials.

Yet a further object of the invention is to provide a process whereby paints or pigments are combined in situ on an article to mix the paints or pigments to quickly produce an item of furniture and to arrive at a unique finished appearance.

In the process of the invention, all steps are usually carried out manually by an operative. The operative is provided with a number of documents or instructions which describe to the operative the exact procedures to be carried out in accordance with the steps of the process .

Generally, the process of the invention is made up of the following steps: Fabrication An operative is provided with a fabrication schedule, a fabrication cutting list and a drawing of the relevant item of furniture and/or furnishing.

Where a metal raw material such as steel is used, using the relevant cutting list, an operative cuts the raw material on a band or circular saw in accordance with the production schedule.

Following cutting of the metal raw material in accordance with the production schedule, the operative then applies a quality control procedure to the cut raw material to ensure that the dimensions of the cut raw materials are in conformity with the dimensional tolerances required in the assembled furniture e.g. typically +/- 0.05mm.

Typically, the metal raw material is made up of elongate lengths of steel or aluminium which is cut to the desired length by an operative.

Following cutting of the metal raw material to the required dimensions, the metal raw material is deburred by the operative with a sander. A number 36 grit pad has been found to be particularly effective for deburring. However, the number of the grit pad utilized in the deburring operation can be selected in accordance with the finish required.

Following cutting and deburring, the components are stacked by an operative in sets to be assembled in accordance with the fabrication schedule. The sets of components are subsequently conveyed to an individual welding bay.

The components of the raw material are then assembled using welding methods.

A welding jig, tack and mig seam weld is typically utilized to sub-assemble the components in accordance with the specification. During sub-assembly it is ensured that distortion of the components does not occur. The sub-assembly components of the item of furniture are then assembled also using welding methods .

The dimensional conformance of the assembled piece of furniture is then determined. The assembled piece of furniture or furnishing is then stored for the subsequent steps in the manufacturing process.

Timber assembled items of furniture can be assembled in conventional manner using conventional techniques.

Shotblastinq Assembled items of metal furniture are then shotblast by an operative in accordance with a shotblasting schedule .

Shotblast of the metal raw material is required in order to prepare the metal surface to receive paint materials. More particularly, it is necessary to shotblast metal materials in order to remove contaminants, corrosion and grease from the metal surface which can prevent finishing materials such as paints and pigments from adhering to metal surfaces.

In addition, it has been found that shotblasting of the metal surface causes distress to the metal surface which enhances bonding and adhering of paint materials to the surface for the production of an item of furniture having a reproducibly mottled, marbled or distressed appearance.

The assembled products are typically installed in a shotblasting booth. The assembled products are shotblast at 90 PSI to prepare the surface of the metal material to accept finishing materials such as paints.

It has been found that a G34 metal grit material produces a particularly useful metal surface for bonding and mixing paints and pigments thereon.

The shotblast assembled product can then be stored for the next step in the process. Alternatively, the assembled product can be treated immediately as outlined below: Cellulose painting Where metal raw material has been utilized in the assembly of the assembled product, the item is installed by the operative in a paint booth and primed with an etch primer/activator. It has been found that an etch primer/activator ratio of 50:50 is particularly useful in achieving a consistent finish and desirable distressed appearance. Following application of the primer/activator, typically with a spray gun, the item of furniture is dried at room temperature for a period of approximately two to four hours.

It is not necessary to apply an etch primer/activator to assembled items of furniture manufactured from timber material as the etch primer/activator serves to prevent rusting of metal materials .

A first paint or pigment mixture is then applied to the assembled product. The first paint is applied to both timber and metal based assembled items. It has been found that the first paint or pigment conveniently comprises a base coat. However, unlike conventional base coats, the base coat used in the process of the invention is formulated to mix and run with a final coai in situ on the item of furniture to arrive at a unique finish. This shall be explained more fully below.

It has been found that a base coat comprising a metal cellulose paint/thinners/matting agent combination is particularly effective in arriving at a finished item of furniture. Typically the ratio of metal cellulose paint/thinners/matting agent found to be particularly effective is a ratio of 60:30:10. The exact ratios to be used can be selected in accordance with the appearance required of the finished product.

It has been found that, where insufficient thinners is utilized and the ratio of paint to thinners increased excessively, the paint can cause clotting of the base coat resulting in an undesirable end finish. However, if the level of thinners is excessive, the base coat can be too thin resulting in a base coat that will not adhere to the surface on the assembled product.

The matting agent is used to reduce the gloss-level of the cellulose based paint. The base coat is applied to the assembled item under pressure. The pressure used to apply the base coat is important in order to obtain the desired level of adherence of the base coat to the item of furniture. A pressure of 45 p.s.i. has been found to be particularly effective in applying the base coat to the assembled product.

Following application of the base coat to the assembled product the product is dried at room temperature for a period of approximately two to four hours.

Finishing painting Following drying of the assembled product for a period of approximately two to four hours, a hand painting operation with a brush is carried out on the product to mix the base coat with a finishing coat in situ on the assembled product. Conventional wisdom teaches that it is undesirable for a base coat and a finishing coat to mix/combine or run into each other in situ. However, it has now been found that such mixing results in an item of furniture having a unique and reproducible distressed appearance which is substantially independent of the material to which the base coat and finishing paint is applied.

The period used to dry the item of furniture following application of the base coat is critical. Hand painted finishing requires the finishing coat to break-up the base coat on the item of furniture. Accordingly, if the base coat has been allowed to dry for an excessive period i.e. greater than approximately four hours break-up of the base coat will not occur while insufficient drying of the base coat i.e. less than approximately two hours can result in excessive dilution of the base coat by the finishing coat to result in an item of furniture with a matt appearance without a mottled or distressed effect.

An operative utilizes a production schedule, drawing of the item of furniture and a test card showing the desired appearance of the finished surface as a control.

The assembled product having a base coat applied thereto is located by the operative beneath a ventilation duct. Observing the production schedule and test card, the operative then applies by hand a finishing coat. It has been found that a finishing coat made up of a cellulose paint mix and thinners is particularly effective at arriving at a stressed/mottled appearance. The thinners serve to facilitate the break-up of the base coat in situ.

As previously indicated in relation to the base coat, the ratio of cellulose paint mix and thinners is critical in order to achieve the desired end result.

It has been found that a ratio of 15:85 cellulose mix/thinners is particularly effective at covering exterior surfaces of the assembled timber or metal products .

The level of thinners utilized in the final base coat is critical as the level of thinners determines the degree of break-up of the base coat and accordingly the degree of mixing of the finishing coat and base coat to arrive at the final appearance of the item of furniture .

Following application of the cellulose mix/thinners mix using a hand brush an operator examines the appearance of the item against the test card for conformity to the displayed finish chart.

An operative can vary the amount of cellulose mix/thinners mix applied to the item in order to achieve the desired result and achieve further break-up of the base coat by the final cellulose mix/thinners mix.

The item of furniture is then moved to a final quality control area and allowed to dry for a period of approximately twenty four hours.

The final product is then examined to ensure dimensional and finish conformance in accordance with the production schedule. Reworking of the item of furniture is carried out as required. A label indicating that the item of furniture has passed a quality control procedure is then applied to the assembled item.

Following application of the final coat other operations may be carried out on the item of furniture e.g. application of glass surfaces/table tops etc.

The item of furniture can then be packed in conventional manner for transport.

Suitable etch primers/activators for use with metal substrates is a HP2O one pack pigmented etching primer available from Trimite. However, other etching primers such as SAP3 two pack self-etching primer or CP4O acrylic cellulose primer may also be used for steel substrates. SAP3 can also be used for aluminium substrates .

A preferred paint is C40 high build cellulose finish available from Trimite. The base coat is usually of a paler colour than the finish coat and is made up of the paint, thinners and matting agents. Typical thinners include CT80 also available from Trimite.

The preferred cellulose paint to be utilized in the process of the invention is a Trimite cellulose paint such as C40 high build cellulose finish as supplied by Trimite Paints Limited. All coatings are applied with conventional paint equipment such as sprayers and brushes which should be properly maintained at all times. It is important that all coatings should be applied with moisture free equipment in order to avoid disruption of the finished coating.

The cellulose paint material utilized in the finishing paint of the furniture of the invention is based on cellulose nitrate usually used in the automobile industry. An advantage of the use of cellulose nitrate based paints is the high speed of drying enjoyed with such paints. In addition, the cellulose nitrate finish is reinforced with alkyd resin materials to provide a tough and durable paint finish materials.

Suitable matting agents are cellulose based matting agents such as solution 51 available from Trimite.

The process of the invention can be used for the production of tables, chairs, lamps, mirrors, occasional tables, shelving etc. manufactured from metals such as steel and aluminium and timber such as MDF.

Claims (15)

1. A process for the manufacture of furniture comprising cutting raw material into required shapes, assembling the shapes into an item, applying a base

2. A process as claimed in Claim 1 wherein the base 10 coat comprises a metal cellulose paint mixture.

3. A process as claimed in Claim 2 wherein the metal cellulose paint mixture comprises a mix of paint, thinners and matting agent in a ratio of 16:30:10.

4. A process as claimed in any of Claims 1 to 3 15 wherein the finishing coat comprises a cellulose paint mix.

5. A process as claimed in Claim 4 wherein the cellulose paint mix comprises a mixture of cellulose paint and thinners in a ratio of 15:85. 20 5 coat to the item, applying a finishing coat to the furniture item before the base coat is dry and mixing the base coat and finishing coat in situ on the item of furniture.

6. A process as claimed in any of Claims 1 to 5 wherein the base coat is dried at room temperature for a period of two to four hours before application of the finishing coat.

7. A process as claimed in any of Claims 1 to 6 wherein the finishing coat is dried for twenty four hours at room temperature. 5

8. A process as claimed in any of Claims 1 to 7 wherein the base coat is applied to the item of furniture by spraying.

9. A process as claimed in any of Claims 1 to 8 wherein the finishing coat is brushed onto the item to 10. Steel and aluminium. 17. A process as claimed in any of Claims 1 to 9 wherein the material comprises timber. 18. A process as claimed in Claim 17 wherein the timber comprises MDF.

10. A process as claimed in any of Claims 1 to 9 wherein the raw material comprises a metal. 10 break-up the base coat.

11. A process as claimed in Claim 10 wherein the metal is assembled by welding. 15

12. A process as claimed in Claim 11 further comprising shotblasting the assembled item.

13. A process as claimed in Claim 12 further comprising priming the shotblast assembled item before application of the base coat.

14. A process as claimed in Claim 13 wherein the primer comprises an etch primer and activator mix in a ratio of 50:50. 15. A process as claimed in Claim 14 wherein the etch 5 primer and activator mix is dried at room temperature for a period of two to four hours before application of the base coat. 16. A process as claimed in any of Claims 10 to 15 wherein the metal is selected from the group comprising

15. 19. Furniture whenever manufactured by a process as claimed in any of the preceding claims.