IL27532A

IL27532A - Wood veneers

Info

Publication number: IL27532A
Application number: IL2753267A
Authority: IL
Original assignee: Aaronson Bros Ltd
Priority date: 1966-03-04
Filing date: 1967-03-03
Publication date: 1970-03-22
Also published as: ES336762A1; CH471648A; GR33619B; NL6703054A; BE694830A; DE1628953A1; FR1512758A; ES348888A1; GB1172682A; DK117916B

Description

Patents Form No. 3 PATENTS AND DESIGNS ORDINANCE.

SPECIFICATION.

"IMPROVEMENTS IN OR H IATING TO WOOD VENFERS" 1 / WE ' -AABOISSQ8 BBOS, LIMITED, a ^pi is CoB^amy, do hereby declare the nature of this invention and in what manner the same is to be performed, to be particularly described aud ascertained in and by the following statement : - This invention is concerned with strip vood veneers suitable for providing an edge surface to an article, and to a method of forming such an edge surface using the strip wood veneer.

In the past there has been considerable difficulty in providing edge surfaces to articles, such as timber, boards, plywood and doors, in that it has not proved possible to adhere an edge surface firmly and enduringly to the edge of an article by a simple method which does not require the use of cumbersome and costly machinery-. The present invention provides product which enables such edge surfaces to be applied by a small scale .operator, for example by the ordinary person doing his carpentry work at home.

According to the present invention there is provided strip wood veneer having on one surface a film of material which is non-adhesive at room temperature, but which is capable of being rendered adhesive by application of heat, such as may be produced by a domestic electric iron, so that the strip wood veneer may be firmly adhered to the edge surface of an article by the film of material.

Advantageously the film of material on the one surface of the strip wood veneer is a film comprising an ethylene/vinyl acetate copolymer, preferably with rosi or rosin ester.

The present invention also comprehends a method of applying an edge surface o an article comprising the steps of taking a strip wood veneer which has a width similar to the thickness of the article and which carries on one surface a film of material which is non-adhesive at room temperature, and pressing the strip wood veneer against the edge surface of the article using a heated domestic iron which renders the film of material capable of adhesion by application of heat . thereby adhering the strip wood veneer firmly to the article to constitute the edge surface thereof.

In a preferred method in. accordance with the present invention the length of strip wood veneer necessary to cover the edge surface of the article is first determined., the desired length of strip wood veneer is obtained, and the whole edge surface of the article is then provided by a single application of pressure and heat to the strip wood veneer.

The strip wood veneer in accordance with the present invention may be made and used in a range of widths to correspond with different thiclmesses of the articles on which an edge surface is to be formed.

The strip wood veneer may be formed in a roll of very substantial length, for example the roll may be of several hundred feet in length and such a roll is obtained by joining together successive lengths of strip wood veneer, which may be a natural or an artificial veneer, before the film of a material used in the adhesion is applied to the veneer.

Advantageously the considerable lengths, for example 200' to 500', of strip wood veneer in a roll are made by taking a series of lengths of strip wood veneer and forming a zig-zag edge of projections or fingers to each end of each length of strip wood veneer.

The ends of the successive lengths of strip wood veneer are then arranged so that the zig-zag edges of adjacent strip wood veneers interlock and are retained in an interlocking position while the material which is capable of adhesion at an elevated temperature is applied to one surface of the successive lengths of strip wood veneer.

It is not essential that the interlocked ends of the successive lengths of strip wood veneer be joined together in a permanent manner, provided that they are retained together for a long enough time to permit of the application of a film of material which is capable of performing the subsequent adhesion of the veneer to the article on which it is to be applied. When the projections or fingers on the two zig-zag edges are brought together for joining together of two strip wood veneers, the projections or fingers constitute inter-digitating elements.

According to this feature of the invention, therefore, a strip wood veneer having a length longer than the length necessary to cover the edge surface of the article is obtained by taking a series of lengths of strip wood veneer, forming a zig-zag edge to each end of each length of strip wood veneer, interdigitating the zig-zag edges of successive lengths of strip wood veneer joining together the interdigitating ends of the siccess ive lengths of strip wood veneer, applying to one surfac of the joined lengths of strip wood veneer the material which is capable of adhesion at an elevated temperature, but is non-adhesive at room temperature, and cooling the said material to form a film on the said one surface.

In a preferred method of manufacturing strip wood veneer in accordance with this invention, the material which is capable of adhesion at an elevated temperature, but which is non-adhesive at room temperature, is applied by advancing the strip wood veneer over the upper surface of a first roller which is rotated with the advance of the strip wood veneer and while the first roller has a lower part thereof dipping into a hot melt of the adhesive material, restricting the thickness of the adhesive material raised on the surface of the roller during the rotation by a blade edge located lengthwise of the first roller, so that a desired thickness of adhesive material is imparted by the first roller to the lower surface of the advancing strip wood veneer, and contacting the upper surface of the strip wood veneer advanced over the first roller by a cooled second roller which maintains the strip wood veneer cool and causes the adhesive material applied by the first roller to be at least partially set so that it will not adhere to any exposed surface with which it comes in contact.

Advantageously, before the strip wood veneer carrying the film of adhesive material is stored, it is passed between two further rollers engaging respective surfaces of the strip wood veneer and arranged to ensure that the film of adhesive material is cooled sufficiently to be non-adhesive.

The present invention still further comprehends apparatus for applying a film of adhesive material to a strip wood veneer, the apparatus comprising first and second rollers, the second roller having its axis substantially vertically above the axis of the first roller, and the circumference of the first roller being separated from the circumference of the second roller by a distance approximately equal to the thickness of the strip wood veneer plus the desired thickness of the film of adhesive material, a melt of an adhesive material which exhibits its adhesive qualities only at a temperature greater than room temperature and into which melt the first roller dips, means for rotating both said first and second rollers so that their circumferences are moving at similar velocities, means positioned parallel to the axis of the first roller for controlling the thickness of adhesive transferred by said first roller from the melt to a position on its circum erence near to the second roller, and a cooling system for maintaining the surface of the second roller at a temperature near ambient temperature.

Desirably the apparatus further comprises third and fourth rollers which are situated in a relationship inter se similar to the relationship of said first and second rollers, and which are positioned near to said first and second rollers, one or both of said third and fourth rollers having means for cooling whereby a film of adhesive material present on a strip wood veneer passed between said third and fourth rollers will be cooled to ensure that the film of adhesive material is entirely non-adhesive.

It is very desirable that the relative positions of the first and second rollers and also the third and fourth rollers, if these are provided, may be adjustable so that the apparatus may be employed for applying films of adhesive material to wood veneers of different thicknesses. In order that this may be achieved, apparatus in accordance with the invention preferably has the said first and second rollers mounted in respective lower and upper sections, the position of the sections, and consequently the axes of the said first and second rollers, being controlled by resilient means under compression acting to separate said sections, and the sections being retained in a desired position by mechanical screw means engaging the outer surfaces of said first and second sections against the action of the resilient means .

The present invention also comprehends a roll of strip wood veneer, the strip wood veneer having on one surface a film of material which is capable of being rendered adhesive' by application of heat so that the strip wood veneer may be firmly adhered to another article by the said adhesive after application of heat.

The present invention will be better understood from the following detailed description which is made, by way of example, with reference to the accompanying diagrammatic drawings, in which: - Figure 1 shows a roll of wood veneer in accordance with the present invention, Figure 2 illustrates the manner in which the zig-zag edges formed in the ends of successive lengths of wood veneer are interlocked to form an extended length of wood veneer, Figure 3 illustrates a preferred embodiment of apparatus for applying a film of adhesive material to a wood veneer, and Figure 4 illustrates the manner in which a strip of wood veneer may be applied to form an edging to a rectangular wooden board.

In the drawings, like reference numerals designate the same or similar parts.

Referring first to Figure 1 of the drawings, there is shown a spool 1 partly cut away to reveal a roll 2 of wood veneer 3 having on one surface a film 4 of an ethylene/vinyl acetate copolymer resin containing rosin, which is a material capable of being rendered adhesive by application of heat. The wood veneer is coiled in the roll 2 on the spool 1 so that the film 4 of adhesive material is on the underside of the wood veneer 3· The length of the wood veneer which is rolled upon the spool 1 may be several hundred feet, and this extended length of wood veneer is obtained by integrating together the ends of a considerable number of sheets of wood veneer sliced from a log or sliced from a block which has been made artificially. In Figure 2, there is shown a plan view of successive sections of strip wood veneer 5, 6, 7. These successive sections of wood veneer are joined together by forming in the ends of each of them a zig-zag edge so that there are a series of projections or fingers illustrated as projections 8 on the section 5 of wood veneer, projections 9 on the respective ends of the section 6 of wood veneer and pro-jections 10 on the end of the section 7 of wood veneer.

The projections 8 and 9 on the respective sections 5 and 6 of wood veneer are shown as they are being brought together into interlocking position and the manner in which the projections naturally interdigitate in the interlocking position is illustrated with respect to the projections 9 and 10 on the ends of the sections 6 and 7 of wood veneer. Preferably an application of an adhesive which will endure for at least an hour or two, for example a urea adhesive, is made to the respective projections before they are brought together, and when the projections 9 and 10 are in interlocking relation, the sections of wood veneer 6 and 7 are joined by pressing the interlocking projections 9 and 10 with an application of heat, for example at 100°C. The pressure is only applied with the heat for a matter of a few seconds to effect the joining of the two sections 6 and 7.

The joined lengths of wood veneer may then be coiled on a spool and taken to another section of apparatus where the next stage of the process is performed or alternatively the joined lengths of wood veneer may be passed directly after joining to an apparatus similar to that illustrated in Figure 5, The extended length of wood veneer 11 obtained after joining together successive sections of wood veneer in the manner illustrated in Figure 2 is passed into an apparatus comprising upper and lower sections or boxes 12 and 13 which are maintained in a desired relative position by means including a compression spring 14. The compression spring 14 acts against the surfaces 15 and 16 of the boxes 12 and 13 whose relative position may be varied by an arrangement of a screw 17 and nut 18, the head of the screw 17 and the nut 18 being external of the surfaces 15 and 16 respectively. While only one arrangement of compression spring 14 and screw 17 and nut 18 is illustrated, it will be appreciated that more than one such arrangement may advantageously be provided.

The extended length of wood veneer 11 which is advanced into the middle portion between the two boxes or sections is advanced between two rollers 19 and 20 which are similar in size and which are arranged with their respective axes in the same vertical plane. The adjustment of the compression spring 14 and the screw 17 and nut 18 is such that the distance between the nearest points of the rollers 19 and 20 which are mounted respect-ively in the lower section or box 12 and the upper section or box 13 is substantially equal to the thickness of the veneer to be coated plus the thickness of the film of adhesive which is to be applied to the wood veneer.

Purely as an example, the wood veneer may be 0.6 mm. in thickness, and the film of adhesive applied to the wood veneer about 0.3 mm. thickness, so that the spacing between the nearest points on the circumferences of the two rollers 19 and 20 will in that case be about 0.9 mm.

Also mounted respectively in the lower and upper sections or boxes are two further rollers 21 and 22.

These rollers 21 and 22 are positioned in relation to one another in exactly similar manner to the rollers 19 and 20 as previously described.

Provided within the lower section or box 12 in a position where the roller 19 may have a small part of its lower section immersed in it is a container 23 holding a melt of the adhesive material, for example an ethylene/vinyl acetate copolymer resin containing rosin or rosin ester. The viscosity and flow properties of the melt may be altered by including an inorganic filler, and inhibitors may also be included to protect the melt ingredients against degradation at elevated temperatures. The melt of the adhesive material is at a temperature at which the material is adhesive, for example 130°C.

The roller 20 is connected via a feeding means, for example a sponge 24, to a source of cold water which keeps the roller 20 at a low temperature so that this low temperature is continually applied to the upper surface of the extended length 11 of wood veneer passing between the two rollers 19 and 20; the roller 21 is immersed in a bath of cold water so that the temperature of this roller 21 is kept near room temperature and the roller 22 may be cooled in a similar manner to the roller 20, All four rollers 19, 20, 21 and 22, are driven by conventional motors not shown, the rollers 19 and 21 being driven in a clockwise direction and the rollers 20 and 22 being driven in an anti-clockwise direction as seen in Figure 5· As the roller 19 is rotated, so adhesive material is lifted on its surface past a controlling blade 25 positioned parallel to the axis of the first roller 19 and spaced from the surface of the roller 19 by a distance approximately equal to the desired thickness of adhesive material to be applied to the wood veneer, for example 0.3 mm. Consequently the roller 19 brings the desired thickness of adhesive material at an elevated temperature at which the material is adhesive into contact with the underside of the extended length 11 of wood veneer passing between the rollers 19 and 20. The upper surface of the extended length 11 of wood veneer is cooled by the roller 20 and its associated cooling means or sponge 24 so that the contact of the adhesive material with the underside of the extended length 11 of wood veneer causes the adhesive at least partially to set on the lower surface of the extended length 11 of wood veneer, and the adhesive is largely removed from the roller 19 and retained as a film on the lower surface of the wood veneer.

The passage between the cold rollers 21 and 22 of wood veneer carrying on its lower surface a film of the adhesive material ensures that the adhesive material is completely set before the wood veneer carrying the adhesive material is coiled to form a roll 2.

In Figure 4 there is shown a plan view of a substantially rectangular board 26 to the edge or periphery of which a pleasing finish is desired to be applied. In accordance with the present invention, this is done by taking a roll 27 of strip wood veneer and, by hand, un-rolling the strip wood veneer round the whole periphery of the board 26 substantially as illustrated in Figure 4. The desired extended length 11 of strip wood veneer required to edge the whole of the board 26 is then cut from the roll 27. A metal object 28 having a substantially flat heated surface 29, for example an electric iron, is then applied to the upper surface of the wood veneer carefully placed in position along the edge or periphery of the board 26 and this application of pressure and heat causes the strip wood veneer to be firmly adhered through the adhesive material to the periphery or edge of the board 26» In addition to being used in a manual application of edging to a board as described with reference to Figure 4 , the strip wood veneer in accordance with the present prejfetrb invention is also suitable for application by machine in an automatic process.

By use of strip wood veneer substantially as herein described, edging may be applied to peripheries which are not planar and in particular edging may be applied around curves and corners and an excellent firmness of adhesion obtained along all parts of the edge of the base object.

In addition to being used as an edging, the wood veneer in accordance with the present invention may be applied in widths as a surface on a base object.

By using an extended length of wood veneer obtained from a roll, the veneer may be directly applied around the edge of a board of any size at all. The same roll of strip wood veneer will be used for all boards of different sizes, provided that the thicknesses of the boards are suitable.

Although the wood veneer in accordance with the present invention is preferably applied to a wood product, it may equally be applied to products of other materials.

Claims

27532/2 Claims

1. Strip wood veneer having on one surface a film of material which is non-adhesive at room temperature, but which is capable of being rendered adhesive by application of heat, such as may be produced by a domestic electric iron, so that the strip wood veneer may be firmly adhered to the edge surface of an article by the film of material.

2. Strip wood veneer according to Claim 1, comprising natural lengths of strip wood veneer having zig-zag edges and held together by the film of material with zig-zag edges inter-digitated to form a substantial length capable of being stored as a roll of strip wood veneer.

3. J. Strip wood veneer according to Claim 1 or Claim 2 , wherein the film of material on the one surface of the veneer is a film comprising an ethylene/vinyl acetate copolymer.

4. Strip wood veneer according to, Claim 1 or Claim 2 , wherein the film of material on the one surface of the veneer is a film comprising an ethylene/vinyl acetate copolymer; and a material selected from rosin and rosin ester.

5. A method of applying an edge surface to an article comprising the steps of taking a strip wood veneer which has a width similar to the thickness of the article and which carries on one surface a film of material which is non-adhesive at room temperature, and pressing the strip wood veneer against the edge surface of the article using a heated domestic iron which renders the film of material 27532/2 '> -v- capable of adhesion by application of heat, thereby adhering the strip wood veneer firmly to the article to constitute the edge surface thereof.

6. A method according to Claim 5, wherein the length of strip wood veneer necessary to cover the edge surface of the article is first determined, the desired length of strip wood veneer is obtained, and the whole edge surface of the article is then provided by a single application of pressure and heat to the strip wood veneer.

7. A method according to Claim 5, wherein the strip wood veneer used carries a film of material including an ethylene/vinyl acetate copolymer.

8. A method according to Claim J, wherein the film of material additionally includes rosin or rosin ester.

9. A method of applying an edge surface to an article according to Claim 6 wherein the strip wood veneer which is used is first manufactured by a method comprising the steps of taking a series of lengths of strip wood veneer, forming a zig-zag edge to each end of each length of strip wood veneer, interdigitating the zig-zag edges of successive lenths of strip wood veneer, joining together the inter-digitated ends of the successive lengths of strip wood veneer, applying to one surface of the joined lengths of strip wood veneer a material which is capable of adhesion at an elevated temperature, but which is non-adhesive at room temperature, cooling the said material to form a film on the one surface, and thereafter forming a roll of strip 27532/2 wood veneer which carries on the one surface a film of the said material .

10. method according to Claim 9> wherein the material which is capable of adhesion at an elevated temperature, but which is non-adhesive at room temperature, is applied by advancing the strip wood veneer over the upper surface of a first roller which is rotated with the advance of the strip wood veneer and while the first roller has a lower part thereof dipping into a hot melt of the adhesive material, restricting the thickness of the adhesive material raised on the surface of the roller during the rotation by a blade edge, located lengthwise of the first roller, so that a desired thickness of adhesive material is imparted by the first roller to the lower surface of the advancing strip wood veneer, and contacting the upper surface of the strip wood veneer advanced over the first roller by a cooled second roller which maintains the strip wood veneer cool and causes the adhesive material applied by the first roller to be at least partially set so that it will not adhere to any exposed surface with which it comes in contact.

11. A method according to Claim 10, wherein, before the strip wood veneer carrying the film of adhesive material is stored, it is passed between two further rollers engaging respective , surfaces of the strip wood veneer and arranged to ensure that the film of adhesive material is cooled sufficiently to be non-adhesive.