GB1586076A

GB1586076A - Apparatus for the continuous printing of textile webs

Info

Publication number: GB1586076A
Application number: GB2416677A
Authority: GB
Original assignee: Kleinewefers GmbH
Current assignee: Kleinewefers GmbH
Priority date: 1976-06-25
Filing date: 1977-06-09
Publication date: 1981-03-18
Also published as: JPS5432878B2; NL7705099A; DE2628676B1; DE2628676C2; FR2355667A1; ES459515A1; JPS532688A

Description

(54) APPARATUS FOR THE CONTINUOUS PRINTING OF TEXTILE WEBS (71) We, KLEINEWEFERS GmbH of Kleinewefers-Kalanderstrasse, 415 Krefeld, Germany a German Company, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: The invention relates to apparatus for the continuous printing of textile webs in which a porous medium which supports a dye that sublimates under the action of heat, bears on the textile web, and in which there is produced a pressure difference across the textile web to cause an air or gas flow therethrough for ensuring deep penetration of the dye molecules into the textile web.

German Offenlegungsschrift 2 005 186 discloses a method and apparatus for printing textile webs or pieces in which the side of the material which is distal from the dye carrier is under negative pressure and vapours resulting from the heating of the dye carrier and of the textile material are extracted from the material in order to protect surface-sensitive textile webs or pieces, in particular knitted fabric containing synthetic fibres, and to facilitate the deeper penetration of the dye into the textile web or textile piece.

To increase the depth of penetration of the dye into the textile material, more particularly in the case of ling-pile carpets or pile material, but also for dense material such as felt, it is also known (German Offenlegungsschrift 2 156 154 and French Patent Specification 2 214 263) to employ a porous dye carrier and to produce a pressure difference across the textile web covered with the dye carrier so that air or gas can flow from the outside of the dye carrier to the outside of the textile web. In this case the web of material and the dye carrier pass through a housing which is divided into a top chamber and a bottom chamber (French Patent Specification 2 214 263). In the previously described known methods and apparatus heat is applied to the dye carrier and to the textile web or textile piece by means of heat radiators which are disposed on the side of the dye carrier which is distal from the textile web.

These cannot produce a heating effect which is precisely definable for the sublimation process in large area processing of the textile web, for example a carpet web of 3 to 5 m width, or alternatively it is necessary for substantial means to be employed to achieve a corresponding heat action over the large continously moving surface area of the textile web.

It is an object of the invention to provide apparatus in which the heat necessary for optimum sublimation is applied over a large surface area to a continously moving textile web and a dye carrier web.

The present invention provides apparatus for the continuous transfer printing of a textile web, comprising a horizontally extending housing containing a treatment chamber, an air or gas-pervious conveyor belt which passes through the housing and divides it into upper and lower portions which belt serves to convey a textile web through the housing, means for passing through the housing a transfer-printing dye carrier in contact with the web in operation, the said upper portion being provided with lateral seals at the sides of the path of the conveyor belt, web and dye carrier, and the treatment chamber having web entry and exit seals, an auxiliary chamber or bypass which interconnects the said two portions of the treatment chamber, a fan in the auxiliary chamber for circulating air or gas, in operation, through the said two portions and through the dye carrier, web, and conveyor belt, and heating means for heating the circulating air or gas.

Advantageously, the temperature of the air or gas stream prior to flowing through the dye carrier and through the textile web is between 5 and 20% higher than the sublimation temperature (in "C) of the dye in the dye carrier.

The air or gas stream is circulated through the auxiliary chamber or bypass and through the treatment housing.

The air or gas stream is recirculated preferably accompanied by repeated cleaning, so that the heat content of the air or gas stream is not lost and it is merely necessary to provide on each circulation slight reheating for the air or gas stream to the desired temperature above the sublimation temperature of the dye in the dye carrier. This is therefore particularly economical when compared with radiant heating systems.

In addition to heating the air or gas stream it is possible for the dye carrier and the textile web to be heated in known manner by radiation. The supply of heat can thus differ over the length and width of the textile web and/or textile web portions or can be optionally varied.

In a further embodiment the textile web and the dye carrier can first be heated by radiant heat and/or a first air or gas stream to a temperature below the dye sublimation temperature after which the first mentioned heated air or gas stream is passed through the dye carrier and through the textile web.

Advantageously, an inlet and exit port for supplying fresh gas or air for discharging spent gas or spent air can be provided at a suitable place.

In a further embodiment of the invention the housing can be divided into two regions situated one following the other and sealed with respect to each other, in which the air or gas stream is conducted through the dye carrier and the textile web under different conditions (heating up, flow velocity).

Two embodiments of apparatus according to the invention are illustrated in the accompanying drawings, by reference to which the invention will be further explained and in which: Figure 1 is a vertical cross section through one embodiment of the apparatus according to the invention Figure 2 is a section along the line II-II of Figure 1; and Figure 3 is a longitudinal section showing another embodiment in which the treatment housing is divided into several portions.

The apparatus shown in Figures 1 and 2 comprises a housing which is subdivided into a treatment chamber 2 and into an auxiliary chamber 3. The front wall 4 of the treatment chamber 2 has an inlet port 5 with sealing means, not shown, and an exit port 7 is disposed in the rear wall 6 and also provided with sealing means. The width of the ports 5 and 7 is selected so that an endless carrier belt, guided over reversing pulleys 9, 10, 11 and 12 and supported by a further pulley 14 on each middle bottom section 13, can be guided into and out of the chamber 2. The pulleys 9, 12 and 10, 11 can be driven in pairs so that the endless carrier belt 8 is set into circulation in the direction of the arrow 15.

The carrier belt 8 is a grid or mesh belt with the necessary load-bearing capacity and tensile strength and is preferably constructed of material which has good thermal conductivity.

The ports 5 and 7 also permit the passage of the textile web 17 to be printed in the treatment chamber 2, which is drawn off from a reel 16 and is drawn out of the apparatus via pulleys 18, 19. When passing through the chamber 2, the textile web 17 rests on the carrier belt 8, both edges of which are supported by or slide along the top edge 20 of two seal strips 21 of curved cross section. A similar strip 22 can be disposed along the middle of the chamber 2.

A strip of printing dye carrier 25 is drawn off in the direction of arrow 24 from a reel 23, is guided through the chamber 2 together with the textile web 17, and after leaving the printing chamber 2 is coiled onto a reel 26. While passing through the chamber 2 the dye carrier 25 bears closely upon the top of the textile web 17. The dye carrier 25 is porous and on the side nearest to the web 17 it carries a dye which can be sublimated.

Near the side walls 27, 28 of the chamber 2, which is divided in the horizontal plans by the strips 21 and the carrier belt 8 with the textile web 17 and dye carrier 26 bearing thereon into a top chamber portion 29 and a bottom chamber portion 30, there are provided slotted link members 31, 32, which are slidable on vertical rods, not shown, and have external sealing plates 33, 34 mounted thereon the bottom 35,36 of each of which bears upon the dye carrier 25 or whose bottom end is oriented towards the dye carrier 25. The angular positions of these plates in relation to the walls 27, 28 are adjustable. The adjustment of the plates 33, 34 defines the processing width of the textile web 17, the processing width being defined by the bottom ends 35,36 of the plates 33,34.

As shown in Figure 1, the two plates 33, 34 can have different angular positions. For example, the processing width of the textile web can be increased if the plate 34 is set to a steeper angle.

The bottom chamber portion 30 has a port 37 the opening of which is adjustable and which merges into a chimney-like extractor portion 38, and also has an inlet port 39, also adjustable, through which fresh gas or air can enter the chamber portion 30 as will be described hereinbelow.

A large-surface filter 41, downstream of which a fan 42 is mounted, is disposed between the bottom chamber portion 30 and the bottom portion 40 of the auxiliary chamber 3, approximately in the plane of the chamber wall 27 which divides the chamber 2 from the auxiliary chamber 3.

The bottom portion 40 of the auxiliary chamber 3 is separated by a heating register 45 from the top portion 43 of the auxiliary chamber, which communicates through an opening 44 with the top portion 29 of the chamber 2. The flow cross section and the heat output of the said heating register 45 are variable.

The air or gas stream, which circulates through the heating register 45 in the direction of the arrows 46 in Figure 1 and is cleaned by the filter 41 each time it enters the auxiliary chamber 3, is heated to a temperature which is approximately 5 to 20% above the sublimation temperature (in OC) of the dye on the dye carrier 25.

Distribution of the air or gas stream which flows in the arrow direction 46 can be effected by suitable nozzles or perforated plates so that an air or gas stream of uniform quantity and heat content acts over the width and length of the top chamber portion 29 on the dye carrier 25 and on the material web 27, or so that an air or gas stream of irregular surface action is directed onto the film and the textile web.

The air or gas flows from the chamber portion 29 through the dye carrier 25 through the textile web 17, and through the carrier belt 8, in accordance with the porosity of the dye carrier 25 and in accordance with the gas or air permeability of the carrier belt 8, into the chamber portion 30 and from there it is again circulated by means of the fan 42 through the filter 41 and through the heating register 43 into the chamber 29.

In the embodiment according to Figure 3 the textile web 50 is drawn off from a reel 51 and together with the dye carrier 53 which bears on the web and is drawn off from a reel 52 it is first passed on an endless carrier belt 59 through a preheating chamber 54 in which the temperature of the printing film and of the web is raised by radiant heaters 55 and air heaters 56 to a value which is 20 to 40% below the sublimation temperature of the dye on the printing film. In an adjoining vestibule chamber 57 a heated air or gas stream 58 is directed downwardly through the dye carrier and through the textile web as described with reference to Figures 1 and 2. The carrier belt 59 can have the same construction as the carrier belt 8 of Figures 1 and 2.

The web 17 and the printing film 53 are heated in the vestibule chamber 57 by means of the air or gas stream 58 to a temperature close to the limiting value defined for a temperature-sensitive textile web. For example, if the sublimation temperature of the dye is approximately 1900, but the textile web will already suffer damage at 1700, the dye carrier and the web will be heated to a temperature of approximately 1600 in the vestibule chamber 57 by means of the gas and air stream which can be very accurately regulated and adjusted.

A quantity of heat by means of which the temperature of the dye of the dye carrier 53 is raised in a short time to the sublimation temperature is then supplied to the treatment chamber 60 while heating of the substantially thicker textile web is not extended beyond the temperature at which the web is damaged, in the above example 1700. Radiant heaters 61 as well as means which allow a heated air flow 62, produced as in the case of Figures 1 and 2, to act on the dye carrier web and on the textile web are provided in combination in the treatment chamber 60.

The textile web can be immediately cooled by suitable coolant means 63 after leaving the treatment chamber 60.

WHAT WE CLAIM IS: 1. Apparatus for the continuous transfer printing of a textile web, comprising a horizontally extending housing containing a treatment chamber, an air or gas-pervious conveyor belt which passes through the housing and divides it into upper and lower portions which belt serves to convey a textile web through the housing, means for passing through the housing a transfer-printing dye carrier in contact with the web in operation, the said upper portion being provided with lateral seals at the sides of the path of the conveyer belt, web and dye carrier, and the treatment chamber having web entry and exit seals, an auxiliary chamber or bypass which interconnects the said two portions of the treatment chamber, a fan in the auxiliary chamber for circulating air or gas, in operation, through the said two portions and through the dye carrier, web, and conveyer belt, and heating means for heating the circulating air or gas.

2. Apparatus as claimed in Claim 1 in which the auxiliary chamber or bypass contains a filter for the air or gas and/or the heating means.

3. Apparatus according to Claim 1 or 2 characterised in that the housing is divided into two treatment regions which are situated one behind the other and are sealed with respect to each other and in which the air or gas stream is conducted through the dye carrier and through the textile web under different conditions (heating, flow velocity).

4. Apparatus as claimed in Claim 1, 2 or 3 in which the said housing contains the auxiliary chamber or bypass and the said two portions of the treatment chamber.

5. Apparatus according to Claim 1, 2, 3 or 4 characterised in that one of the said two portions is provided with a fresh air or fresh gas supply port and/or with an air or gas discharge port.

6. Apparatus as claimed in any of Claims 1 to 5 including means for preheating the textile web and dye carrier.

7. Apparatus for the continuous printing of a textile web, substantially as herein described with reference to Figures 1 and 2 or Figure 3 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. flows in the arrow direction 46 can be effected by suitable nozzles or perforated plates so that an air or gas stream of uniform quantity and heat content acts over the width and length of the top chamber portion 29 on the dye carrier 25 and on the material web 27, or so that an air or gas stream of irregular surface action is directed onto the film and the textile web. The air or gas flows from the chamber portion 29 through the dye carrier 25 through the textile web 17, and through the carrier belt 8, in accordance with the porosity of the dye carrier 25 and in accordance with the gas or air permeability of the carrier belt 8, into the chamber portion 30 and from there it is again circulated by means of the fan 42 through the filter 41 and through the heating register 43 into the chamber 29. In the embodiment according to Figure 3 the textile web 50 is drawn off from a reel 51 and together with the dye carrier 53 which bears on the web and is drawn off from a reel 52 it is first passed on an endless carrier belt 59 through a preheating chamber 54 in which the temperature of the printing film and of the web is raised by radiant heaters 55 and air heaters 56 to a value which is 20 to 40% below the sublimation temperature of the dye on the printing film. In an adjoining vestibule chamber 57 a heated air or gas stream 58 is directed downwardly through the dye carrier and through the textile web as described with reference to Figures 1 and 2. The carrier belt 59 can have the same construction as the carrier belt 8 of Figures 1 and 2. The web 17 and the printing film 53 are heated in the vestibule chamber 57 by means of the air or gas stream 58 to a temperature close to the limiting value defined for a temperature-sensitive textile web. For example, if the sublimation temperature of the dye is approximately 1900, but the textile web will already suffer damage at 1700, the dye carrier and the web will be heated to a temperature of approximately 1600 in the vestibule chamber 57 by means of the gas and air stream which can be very accurately regulated and adjusted. A quantity of heat by means of which the temperature of the dye of the dye carrier 53 is raised in a short time to the sublimation temperature is then supplied to the treatment chamber 60 while heating of the substantially thicker textile web is not extended beyond the temperature at which the web is damaged, in the above example 1700. Radiant heaters 61 as well as means which allow a heated air flow 62, produced as in the case of Figures 1 and 2, to act on the dye carrier web and on the textile web are provided in combination in the treatment chamber 60. The textile web can be immediately cooled by suitable coolant means 63 after leaving the treatment chamber 60. WHAT WE CLAIM IS:

1. Apparatus for the continuous transfer printing of a textile web, comprising a horizontally extending housing containing a treatment chamber, an air or gas-pervious conveyor belt which passes through the housing and divides it into upper and lower portions which belt serves to convey a textile web through the housing, means for passing through the housing a transfer-printing dye carrier in contact with the web in operation, the said upper portion being provided with lateral seals at the sides of the path of the conveyer belt, web and dye carrier, and the treatment chamber having web entry and exit seals, an auxiliary chamber or bypass which interconnects the said two portions of the treatment chamber, a fan in the auxiliary chamber for circulating air or gas, in operation, through the said two portions and through the dye carrier, web, and conveyer belt, and heating means for heating the circulating air or gas.