WO1996008596A1

WO1996008596A1 - Labelling laundry items

Info

Publication number: WO1996008596A1
Application number: PCT/GB1995/002165
Authority: WO
Inventors: William Ashley Baldwin; Remendra Ghandi
Original assignee: Polymark (U.K.) Limited
Priority date: 1994-09-13
Filing date: 1995-09-13
Publication date: 1996-03-21
Also published as: GB9418386D0; AU3480295A

Abstract

A labelling device (1) for laundry items, the labelling device comprising transponder means (3) completely encapsulated within a resin system (4, 5) which has been solidified in situ around the transponder means, and a thermoadhesive layer (7) for use in bonding the device to a laundry item to be labelled.

Description

LABFXLING LAUNDRY ITEMS

The present invention relates to the labelling of laundry items to permit the identification thereof.

Laundered items are commonly labelled either by a temporary mark which is applied to the item when it is checked into the laundry, and removed when the items are checked out after processing, or by a permanent label, which relates to the

customer and the wearer. In this invention we are concerned with the permanent

labelling of laundry items. A prior art permanent label which enables automatic reading and computerised data storage employs bar-coding. Such a label bears a unique bar-code which is scanned into a computerised database management system

which stores all necessary information relating to the item being laundered. A

drawback of bar-coding is that the bar-coded label must be located manually so that it

can be presented to the scanner for reading. In a bundle of soiled garments and linen, this can present a problem.

Transponder devices have previously been proposed for laundry identification.

A transponder is an electronic device providing an identification code for the

laundry item which can be "read" using a transceiver radio device. The transponder provides a unique signal for the garment to which it is attached, the signal being

decoded by the radio device for the purposes of identifying the garment.

The device, when attached to a laundry item, is used in conjunction with non- contact scanning systems which enable the garments to be scanned and individually identified. Such scanning systems may be linked to a computerised database

management system which enables the garments to be tracked through the laundry

and throughout their life.

The use of a transponder overcomes the disadvantages of bar coding, while

retaining the advantages. In addition a transponder device can be used for automatic

routing of the items through the laundry, without there being any need for human

contact in presenting the device to the reader.

The prior art proposals for using transponder devices for labelling laundry

items have involved providing the device in a button in the form of a shell which

comprises two parts glued together. The button was then stitched onto the laundry

item. A limitation of this method is that such devices are lost when thread stitching

the button in place breaks. Also softening of the adhesive during laundering allows

water penetration into the device and resultant failure. A further limitation is that the

limited size restricts the range at which the device can be read.

It is therefore an object of the present invention to obviate or mitigate the

above-mentioned disadvantages.

According to a first aspect of the present invention there is provided a

labelling device for laundry items, the labelling device comprising transponder means

completely encapsulated within a resin system which has been solidified in silll

around the transponder means, and a thermoadhesive layer for use in bonding the

device to a laundry item to be labelled. According to a second aspect of the present invention there is provided a method of labelling a laundry item (e.g. a garment) comprising using heat to bond a device in accordance with the first aspect of the invention by means of its thermoadhesive layer to the item.

According to a third aspect of the invention there is provided a garment having

applied thereto a labelling device in accordance with the first aspect of the invention.

In the labelling device in accordance with the invention, the transponder means is sealed within an encapsulating resin which has been solidified in situ with

the transponder means. This ensures that the transponder means is completely sealed

within the resin system so that ingress of water to the transponder means is not

possible. In other words, the device is wateφroof. The thermoadhesive layer provides a means of securely bonding the labelling device to a garment so that, in

effect, the device is permanently attached thereto.

The encapsulating resin and the thermoadhesive layer are chosen so as to be

substantially unaffected by laundering and dry cleaning chemicals and conditions, as well as by processes such as pressing and calendering. Thus the devices are durable

to repeated laundering and cleaning operations.

The encapsulating resin and thermoadhesive layer should be selected to provide a balance of flexibility (rendering the devices inconspicuous in normal use) combined with stiffness (to prevent damage during laundering). For preference, the

solid encapsulating resin has a Shore A hardness greater than 90 or a Shore D hardness of 50-70. If the Shore A hardness is less than 90 or the Shore D hardness is less than 50 it may be found that the device flexes during the laundry process with resultant damage to the device. A shore D hardness greater than 70 may result in

devices with inadequate bonding to the bonding layer so that the devices may fall off

the garment during laundering.

One embodiment of the device in accordance with the invention comprises the

transponder means within the encapsulating resin which is provided with a layer of a

thermoadhesive film which serves to bond the device to a laundry item by heat and

pressure.

In a further embodiment of the device, the encapsulating resin is laminated to a

permanent carrier to facilitate handling of the device. The permanent carrier may for

example comprise a textile material and is bonded on one face to the encapsulating

resin and on the other face is provided with a thermoadhesive material (e.g. a

thermoadhesive film) for bonding the device to a garment.

Devices in accordance with the invention may be produced by applying a layer

of the encapsulating resin system (in liquid form) to the means providing the bonding

layer (e.g. a thermoplastic film or permanent carrier as discussed above), locating the

transponder means partially in the encapsulating resin and then applying further liquid

encapsulating resin so as completely to enclose the transponder means. The

encapsulating resin is then solidified.

Preferably the encapsulating resin is a cross-linking resin system and the

bonding layer is a thermoplastic material, preferably a thermoplastic film. The thermoplastic film preferably has a thickness in the range of 100 to 200

microns, e.g. about 125 microns.

The cross-linked resin system is preferably a cross-linked polyurethane resin

system produced by reacting a polyurethane resin with a di- or higher- fimctionality

isocyanate. The preferred polyurethane is a polyether polyurethane and the preferred

isocyanate is an aryl di- isocyanate, preferably a diphenyl di-isocyanate, and most

preferably 4', 4"-diphenylmethane di-isocyanate (MDI). Further examples of suitable

di-isocyanates are disclosed in U.K. Patent No. 1 586 511 (Polymark).

Suitable polyurethane resins are available under the name "Hyperlast" (RTM,

a two component polyol/isocyanate polyurethane elastomer supplied by Kemira

Polymers) and "Desmophen" polyurethane resins which is used with "Desmodur"

isocyanate resins. Desmophen and Desmodur (RTM are available from Whitefield

Chemicals Ltd).

A suitable thermoplastic film may for example be of a polyesterurethane or a

polyetherurethane.

Preferably the transponder means comprises a transponder circuit and an

antenna which are arranged generally in a plane so that the transponder means is less

than 1.5 mm in thickness.

Preferably a device in accordance with the present invention has an overall

thickness of less than 3.5 mm and a size less than 40 mm in any other dimension.

Devices greater than about 40 mm in size are likely to suffer damage during

laundering due to increased flexing. Devices greater than about 3.5 mm in thickness are more obtrusive in wear and being stiffer were more likely to be torn off during laundering.

Preferably the device is such that it can be printed on an outer surface with a

durable ink giving human readable information.

The invention will be further described by way of example only with reference

to the accompanying drawings, in which:

Fig. 1 is a plan view of one embodiment of device in accordance with the

present invention;

Fig. 2 is a sectional view of the device of Fig. 1.

Fig. 3 is a cross-sectional view of a further embodiment of a device in

accordance with the present invention; and

Figs 4a and 4b illustrate a jig arrangement for producing devices in accordance

with the invention.

The drawings are to double scale (i.e. the device is shown as twice actual size).

Referring firstly to Fig. 1 and 2, the illustrated device 1 is supported on a

temporary release carrier 2 (e.g. of siliconised paper or the like) and comprises a

transponder means 3 encapsulated within a resin system depicted generally as 4. More specifically, the resin system 4 comprises separately laid down portions 5 and 6

of a cross-linked resin system (e.g. a cross-linked polyurethane) and a facing layer 7

of a thermoplastic film. The portions 5 and 6 are shown separately to depict that, the

liquid cross-linking resin is laid down in two steps but it will be appreciated that the

portions 5 and 6 cure to produce a single block of resin. The transponder means 3 comprises a transponder circuit 8 and an aerial loop

9 (see also Fig. 2) arranged generally in plane so that the transponder means has an

overall thickness of less than about 1.5 mm.

In order to apply the device of Fig. 1 , the temporary carrier 2 is removed and

the device is applied using heat and pressure so as to cause the film 7 to bond the

device to a garment.

A number of modifications may be made to the device illustrated in Fig. 1.

Thus, the temporary carrier 2 may be omitted. Alternatively, the film 7 may be

omitted during the encapsulation process and may be heat bonded to the device after

the temporary carrier is removed and prior to application of the devices to the items

laundered.

The device illustrated in Fig. 3 is similar to that of Fig. 1 and like reference

numerals in the drawings designates like parts. In the device of Fig. 3, the cross-

linked layer 5 is bonded to a fabric 10 which is provided on its face opposite the resin

5 with a film 11 of a thermoplastic resin which has been pre-bonded to the fabric 10.

Fig. 4a is a sectional view of a jig for use in producing a device of the type

illustrated in Fig. 1. Fig. 4b is a plan view of Fig. 4a.

The illustrated jig comprises a steel block 40 having apertures 41 each

defining a mould cavity. The block is held in place by screws 42. A plurality of such

blocks maybe provided in a single jig assembly. As shown in Fig. 4a, the block 40 is

located on an assembly of a release paper 2 and a thermoplastic film 3. To produce

the device of the invention, a first layer of a cross-linkable resin system is introduced into the base of the mould cavity and the transponder means 3 is then located in

position on this resin layer prior to the addition of further cross-linking resin to ensure

complete encapsulation of the transponder means. The cross-linking resin is then

cured.

The following non-limiting Example illustrates the invention.

Example

A jig of the type illustrated in Figs. 4a and 4b was coated with a release

compound and a piece of the Tuftane 310 (RTM: polyester urethane film obtained

from Lord Corporation) was placed on the lower section of the jig. The upper section

(including the mould block) was located in position on the lower section by screws.

The jig was preheated to 50°C as were the containers holding the cross-

linkable resin system described below. This pre-heating reduces viscosity and aids

wetting.

16 parts by weight Hyperlast 2874/213 were mixed with 10 parts by weight

Hyoperlast 2875/046. About 2 ml of the mixture was placed in each section of the

mould and allowed to spread out and cure for 10 minutes. Transponder devices of the

type illustrated in Figs. 2 and 3 were then pressed into the resin in the individual

sections of the mould and a further 2 ml of the resin added to each section, ensuring

complete encapsulation of the transponder. The mould was then placed in a vacuum

oven at 50°C for 30 minutes for the mixture to cure sufficiently for demoulding. The

individual devices were then left overnight to allow full cure. The Shore D hardness

was found to be 60. Suφlus Tuftane film was trimmed off. The devices were inspected for visible defects and the edges were smoothed. The devices were then bonded to cotton and polyester/cotton overalls using a heated press for reading the laundry tests.

A transceiver device was used to verify that the transponder device could be

read at a distance of greater than 10 cm, without the encapsulated transponder being

visible to the operator.

Laundry tests were carried out in a domestic automatic washing machine running at 90°C and using alkaline detergent blends as used in commercial laundries.

During 50 wash and dry cycles the devices were tested for transceiver reading and for

evidence of failure in the wash by detachment, cracking, folding, water penetration,

etc.

The devices stood the 50 washes without such failure and could still be read by

the transceiver device at a distance greater than 10 cm.

Claims

1. A labelling device for laundry items, the labelling device comprising

transponder means completely encapsulated within a resin system which has been

solidified in situ around the transponder means, and a thermoadhesive layer for use in bonding the device to a laundry item to be labelled.

2. A device as claimed in claim 1 wherein the solid encapsulating resin has a

Shore D hardness of 50-70.

3. A device as claimed in claim 1 or 2 wherein the encapsulating resin is a cross-

linked resin system.

4. A device as claimed in claim 3 wherein the encapsulating resin is a cross-

linked polyurethane resin system.

5. A device as claimed in claim 4 wherein the resin system is a cross-linked

poly ether polyurethane.

6. A device as claimed in claim 4 or 5 wherein the polyurethane resin has been

cross-linked with an aryl diisocyanate.

7. A device as claimed in any one of claims 1 to 6 wherein the thermoadhesive

layer is provided by a thermoplastic film.

8. A device as claimed in claim 7 wherein the thermoplastic film has a thickness

in the range of 100 to 200 microns.

9. A device as claimed in claim 7 or 8 wherein the thermoplastic film is a

polyesterurethane or a polyetherurethane.

10. A device as claimed in any one of claims 1 to 9 wherein the thermoadhesive

layer is bonded directly to the encapsulating resin.

11. A device as claimed in any one of claims 1 to 9 wherein the encapsulating

resin is laminated to one surface of a carrier, the other surface of which is provided

with the thermoadhesive layer.

12. A device as claimed in any one of claims 1 to 1 1 wherein the transponder

means comprises a transponder circuit and an antenna which are arranged generally in a plane so that the transponder means is less than 1.5 mm in thickness.

13. A device as claimed in any one of claims 1 to 12 having an overall thickness

of less than 3.5 mm and a size less than 40 mm in any other dimension.

14. A method producing a device as claimed in claim 1 comprising applying a

layer of the encapsulating resin system in liquid form to the means providing the

bonding layer, locating the transponder means partially in the encapsulating resin,

then applying further liquid encapsulating resin so as completely to enclose the

transponder means and solidifying the encapsulating resin.

15. A method of labelling a laundry item comprising using heat to bond a device

as claimed in any one of claims 1 to 13 by means of its thermoadhesive layer to the

item.

16. A garment having applied thereto a labelling device in accordance with any

one of claims 1 to 13.