IES20110149A2 - Processes and apparatuses for applying foils to substrates - Google Patents

Abstract

A method of producing a foiled article by cold foiling onto a substrate is provided in which a substrate web and foil web are fed into a hot foiling machine along a pair of paths, with the foil path bypassing the hot foiling cylinder of the machine, the two paths converging to adhere foil to the substrate with an adhesive and to cure the adhesive, before separating the foil from the substrate, leaving a pattern adhered on the substrate. The advantage is that a single machine can be used for hot and cold foiling, with significant increases in speed and decreases in cost when the cold foiling mode is employed and the hot foiling mode is bypassed. <Figure 1>

Description

for applying foils to substrates Technical Field This invention relates to processes and apparatuses for applying foils to substrates, and in particular to cold foiling.

Background Art Various methods of foiling are known, with the two main categories being hot foiling and cold foiling. In hot foiling, a heated foiling cylinder is used to apply a pattern embossed on the cylinder surface onto foil and thereby transfer that pattern in foil onto a substrate, typically paper.

Cold foiling involves is more akin to a printing process, in that a flexible plate carrying the required pattern (e.g. a Cyrel plate) is used to pick up adhesive, which is impressed onto the surface of the substrate in the required pattern for the foil decoration. A foil sheet is applied over the adhesive pattern, and the combined foil and substrate are passed through a curing process (typically using a fast UV curing reaction) before separating the foil sheet, minus the foil which has been adhered onto the substrate, from the substrate.

Cold foiling has some drawbacks, in particular if fine detail is required in the foil pattern, but it is a much quicker and cheaper process. For example, mounting a plate on a print cylinder for cold foiling, can be done in a couple of minutes. In comparison, mounting and making ready a hot foil cylinder can take an hour or more.

Hot foiling requires pre-heating adding further time before the machine is ready for use.

The cost of a hot foiling cylinder is about ten times that of a cold foil plate. Once the process is running, the run speed for a cold foiling machine is approximately 50% faster than for a hot foiling machine.

IE 11 tt 14 9 In order to cater for diverse requirements of all types of foiling jobs at the optimum speed and price, it is usually necessary to have both hot foiling and cold foiling machines available, In a typical label producing facility, at least 20% and more likely 25% of jobs can make use of the cold foiling machine with its attendant advantages and cost savings. However, carrying both machines has an associated cost and there may be long print runs of one or other foiling type, during which the other machine type may lie idle.

Disclosure of the Invention There is provided a method of producing a foiled article by cold foiling onto a substrate, comprising the steps of: providing a feed of a substrate web into a hot foiling machine; providing a feed ofa foil web into said hot foiling machine; bringing a surface ofthe substrate into contact with a roller carrying a patterned surface covered in adhesive, whereby the adhesive is transferred to the substrate in a desired foil pattern bringing the foil web into contact with said surface of said substrate to adhere the foil web in a pattern to the substrate; curing said adhesive using a photo-curing process; separating said foil web from said substrate to leave a pattern of adhered foil on said surface of said substrate and thereby provide said foiled article; collecting said foil web and said substrate on respective take-up mechanisms; wherein the path of the foil web between the feed and the take-up bypasses the hot foiling cylinder ofthe machine.

There is also provided a foiled article produced according to said process.

It will be appreciated that the method of the invention enables a far more economical method of producing cold foiled articles by employing the infrastructure of a hot foiling machine, adapted to bypass the hot foiling cylinder by using an alternative path through the machine and to include a cold foiling process along that alternative path. 110149 In this way, the machine can be converted between hot and cold foiling operations as desired and as required, without the expense of having two machines and without leaving one machine idle while another is in operation. This provides significant benefits to an organisation which is required to fill various jobs., some of which require the greater detail of hot foiling and others of which can be more quickly and cheaply completed using cold foiling.

There is also provided a method of modifying a hot foiling machine, comprising the steps of: providing a feed for a foil web; providing a roller for carrying a cold foiling plate and a mechanism for bringing a foil into contact with a substrate on said roller; providing a curing station for curing an adhesive pattern bonding said foil to said substrate; providing a separation mechanism for separating the foil from the substrate; and providing a take-up mechanism for the foil subsequent to separation; wherein the path of the foil web between the feed and the take-up bypasses the hot foiling cylinder of the machine.

There is further provided an apparatus for hot and cold foiling, comprising: a feed for a substrate web; a feed for a foil web; a take-up for the substrate web; a take-up for the foil web; a first path between the feed for the foil web and the take up for the foil web in which the foil web is brought into contact with the substrate within a cold foiling mechanism of the apparatus; a second path between the feed for the foil web and the take up for the foil web in which the foil web is brought into contact with the substrate within a hot foi ling mechanism of the apparatus; IE 11 Ο 1 4 9 whereby the same apparatus can be employed in a cold foil mode or a hot foil mode by feeding the foil web through the first path or the second path respectively.

Brief Description of the Drawings The invention will now be further illustrated by the following description of embodiments thereof, given by way of example only with reference to the accompanying Drawing, in which: Fig. 1 is a schematic representation of a foiling machine, shown in terms of paths defined between rollers.

Detailed Description of Preferred Embodiments In Fig. 1 there is indicated, generally at 10, a schematic representation of a foiling machine. The supporting structure of the machine is omitted for clarity, and the machine’s functionality is thus represented by a series of rollers defining paths for foil and substrate webs. Furthermore, the machine is an adaptation of a hot foiling machine, whose normal functionality (i.e. hot foiling cylinder, heating mechanism, etc,) is denoted figuratively by a box 12, it being understood that in a hot foil mode of operation a conventional path through this hot foiling process is provided for both foil and substrate webs, the operation of such a hot foiling machine being well known to the skilled person.

For clarity, the paths of the various webs through the machine are represented using different line types. The foil web 14 is represented in a solid line between a feed roll 16 and take-up roll 18, The substrate web 19 is represented in a broken line between a feed input point 20 and take-up output point 22, and a path section in which the foil web and substrate web are in contact with one another is represented using a double line 24. It is to be understood that the substrate web 19 at the output point is taken to include the substrate carrying the adhesive and a pattern of adhered foil, and the foil web 14 at the take-up roll 18 is taken to mean the foil web minus the portion of foil removed in the foiling process. Arrows parallel to the various webs denote the direction of travel.

IE 11014 9 In use, a patterned flexible plate is mounted around a print cylinder 26. The plate has an embossed pattern, i.e. raised surface portions in the pattern of foil required to be applied to the substrate 19. As denoted by the notation “ADH”, an adhesive take-up mechanism (not shown) is provided to coat the outer surface of the substrate web 19 as it passes over the plate on the print cylinder 26. The adhesive is a UV curable adhesive. (One suitable such adhesive take-up mechanism is a bath of adhesive with a transfer roller partly immersed in the bath, with the transfer roller emerging from the bath as it rotates to press against the substrate.) The substrate web 19 is thus fed along a path (herein referred to as the “second path”) via a first path-defining roller 28 onto and over the print cylinder 26, where it is coated with adhesive. The foil web 14 is similarly fed along a path (the “first path”) via second and third path-defining rollers 30,32 to a pinch roller 34 which applies pressure on the foil against the adhesive coated substrate. The embossed pattern on the plate provides the required pressure to adhere the foil against the substrate in the required pattern.

The combined substrate and foil 24 travel down to a curing roller 36 which is illuminated by a UV source 38 which cures the adhesive pattern, and from here, over a fourth path-defining roller 40 to a separation roller 42 which forces apart the substrate 19 (with the adhered pattern of foil) and the remainder ofthe foil web 14.

After separation, the foil web travels around fifth to ninth path-defining rollers 44,46,48,50,52 respectively, to the take-up roll 18. Similarly, the substrate web 19 travels via tenth to thirteenth path-defining rollers 54,56,58 respectively, to the takeup outlet point 22,

Claims (7)

Claims

1. A method of producing a foiled article by cold foiling onto a substrate, comprising the steps of: 5 providing a feed of a substrate web into a hot foiling machine; providing a feed ofa foil web into said hot foiling machine; bringing a surface of the substrate into contact with a roller carrying a patterned surface covered in adhesive, whereby the adhesive is transferred to the substrate in a desired foil pattern 10 bringing the foil web into contact with said surface of said substrate to adhere the foil web in a pattern to the substrate; curing said adhesive using a photo-curing process; separating said foil web from said substrate to leave a pattern of adhered foil on said surface of said substrate and thereby provide said foiled article; 15 collecting said foil web and said substrate on respective take-up mechanisms; wherein the path of the foil web between the feed and the take-up bypasses the hot foiling cylinder of the machine.

2. A method as claimed in claim 1, wherein the path of the substrate web follows 20 a different path through the machine than when used for hot foiling.

3. A method as claimed in claim 1 or 2, wherein said substrate is a paper web comprising a plurality of labels each of which is patterned with foil. 25

4. , A method of modifying a hot foiling machine, comprising the steps of: providing a feed for a foil web; providing a roller for carrying a cold foiling plate and a mechanism for bringing a foil into contact with a substrate on said roller; providing a curing station for curing an adhesive pattern bonding said foil to 30 said substrate; providing a separation mechanism for separating the foil from the substrate; and IE 1 1 ο 1 4 9 providing a take-up mechanism for the foil subsequent to separation; wherein the path of the foil web between the feed and the take-up bypasses the hot foiling cylinder of the machine.

5. 5. An apparatus for hot and cold foiling, comprising: a feed for a substrate web; a feed for a foil web; a take-up for the substrate web; a take-up for the foil web;

6. 10 a first path between the feed for the foil web and the take up for the foil web in which the foil web is brought into contact with the substrate within a cold foiling mechanism of the apparatus; a second path between the feed for the foil web and the take up for the foil web in which the foil web is brought into contact with the substrate within a hot

7. 15 foiling mechanism of the apparatus; whereby the same apparatus can be employed in a cold foil mode or a hot foil,