CA1066470A - Equipment for use in the manufacture of web material - Google Patents
Equipment for use in the manufacture of web materialInfo
- Publication number
- CA1066470A CA1066470A CA243,119A CA243119A CA1066470A CA 1066470 A CA1066470 A CA 1066470A CA 243119 A CA243119 A CA 243119A CA 1066470 A CA1066470 A CA 1066470A
- Authority
- CA
- Canada
- Prior art keywords
- web
- roll
- thermoplastic material
- softening point
- cooling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21G—CALENDERS; ACCESSORIES FOR PAPER-MAKING MACHINES
- D21G1/00—Calenders; Smoothing apparatus
- D21G1/0073—Accessories for calenders
- D21G1/0093—Web conditioning devices
Landscapes
- Paper (AREA)
- Shaping Of Tube Ends By Bending Or Straightening (AREA)
- Reinforced Plastic Materials (AREA)
- Nonwoven Fabrics (AREA)
- Treatment Of Fiber Materials (AREA)
- Laminated Bodies (AREA)
Abstract
Abstract of the Disclosure A method of, and apparatus for, consolidating and surface finishing a web of intermeshed fibres. At least a proportion of the fibers are of a synthetic thermo-plastic material. The method comprises heating the web to a temperature above the softening point of the synthetic thermoplastic material. Subsequently cooling the web from a temperature above the softening point of the synthetic thermoplastic material to a temperature below the softening point of the synthetic thermoplastic material while the web is in contact with a forming surface. The finish of the forming surface is imparted to the surface of the web during cooling. The web is supported through-out the time it is above the softening point of the synthetic thermoplastic material. The apparatus comprises means for supporting the web and for heating the web while so supported to a temperature above the softening point of the synthetic thermoplastic material. Means for cooling the web from a temperature above the softening point of the synthetic thermoplastic material to a temperature below the softening point of the synthetic thermoplastic material while the web is supported on a forming surface having a surface finish. The surface finish is imparted to the surface of the web. The invention permits the production of a partially or wholly consolidated sheet. Further consolidation is carried out by heat rather than pressure.
Description
This invention relates to a method and apparatus for heat treatment of a web containing fibres of thermo-plastic material.
Paper webs have traditionally been formed from cellulosic fibre derived from various material of vegetable origin, for example woodpulp. More recently proposals have been made for the production of so-called synthetic wood pulp fibres from various polymeræ. Such fibres have a gross morphology, ie. length:diameter ratio, and diameter of the same order of magnitude as cellulosic papermaking fibres derived from woodpulp. They are distinguished from most synthetic textile fibres by their gross morphology and diameter.
The use of synthetic fibres in papermaking affords the possibility of producing webs with novel properties.
One such possibility, provided the synthetic fibres are of a thermoplastic material, is that of heat treatment to soften the fibres, and thereby to produce a partially or wholly consolidated sheet.
It is an object of the invention to provide an improved method for heat treatment of a web of intermeshed fibres at least a proportion of which are of a synthetic thermoplastic material.
According to a first aspect of the invention, there is provided a method of continuously consolidating and surface finishing a paper web substantially all the fibres of which are of a synthetic thermoplastic material, com-prising the steps of heating the web to a temperature above the softening point of the synthetic thermoplastic material, B
the web being supported throughout the time it is above the softening point of the thermoplastic material, and sub-sequently cooling the web from a temperature above the softening point of the synthetic thermoplastic material to a temperature below the softening point of the thermoplastic material while the web is in contact with a forming surface, so that the finish of the forming surface is imparted to the surface of the web without subjecting the web to substantial pressure during the time it is so supported.
In a further aspect the invention is a consoli-dated surface finished web produced by the above method.
It will be appreciated that the present method consolidates the web by the action of heat rather than pressure, as is discussed more fully hereafter.
,~
Preferably, the web is heated by passage round part of the circumference of a heating roll. The roll may be heated for example by hot oil or steam, but the former is preferred as steam presents more S problems o~ pressure sealing.
Preferably, the web is cooled by passage round part of the circumference of a cooling roll, the surface of which constitutes said forming sur$ace.
The cooling roll may be at a temperature below the soitening point of the thermoplastic material of which the fibres are made, but still considerably in excess oi ambient temperature, or it may be at or below ambient temperature. If the cooling roll is to be chilled, air or cold water may be used. The choice of temperature ~or the cooling roll depends largely on the nature of the web and on process parameters, as will be discussed more fully hereafter.
The cooling roll finish, which is imparted to the web, may take various ~orms. For example, it may be a high gloss ~inish, a matt ~inish, obtained ~or example by shot-blasting, or an engraved ~inish.
Advantageously, the web is transferred ~rom the heating roll to the cooling roll by means of a trans~er roll running in contact with both the heating and cooling 2S rolls. Tbe transier roll has a resilient covering, for example of rubber, so that in passing between a nip formed by the transfer and cooling rolls, the roll will not be subjected to heavy pressure which prevents the 106~i~70 achievement of the desired web properties. Although the resilient surface of the transfer roll gently presses the web against the surface of the cooling roll, the pressure is much less than that used in conventional hot pressing processes. As a result of the gentle pressing of the web against the surface of the cooling roll, imparting of the surface finish ~ oi the cooling roll to the web is facilitated. The ; way in which the surface finish is imparted to the web is analogous to a casting process, in that the softened thermoplastic material "flows" and thereby accurately adopts the finish of the supporting surface.
, Once the web has been heated to a temperature above the softening point of the thermoplastic material of which the fibres are made, the web has little coherence. Consequently, it is necessary for the web to be supported until it is again at a temperature some way below the softening point. I~ the web were unsupported when above or very near the softening 20 ~ point, it would be likely to break, stretch or be otherwise deformed.
The coherence o$ the softened web depends to some extent on the extent of consolidation required in the finished web, and on whether it contains a proportion of non-thermoplastic fibres, e.g. cellulosic fibres.
If only partial consolidation is being carried out, or coherence ie imparted by the presence o~ non-thermoplastic fibres, it may be possible to support the web on air jets.
~ - 5 - Otherwise, a supporting member or members is required.
The type of support which will su~fice wilI be readily apparent to the skilled worker in the ar~.
A ~urther consequence o~ the lack of coherence oi the softened web is that if the web is to be transferred from one support member to another while in a soit state, the support member from which the web is being transferred must be treated to facilitate release of the web. Desirably this is achieved by means of a release coating, preferably o~ polytetra-i'luoroethylene. A problem associated with release coatings for use in the present method and apparatus i8 that they cannot have a high gloss i'inish or an engraved ~inish,so i'ar as is known at present. Hence in order to achieve such a finish, the web must be transferred while still soi't to a supporting sur~ace having the desired finish, and on which the web is cooled to a temperature at which it has the coherence necessary to be drawn of~ the supporting suriace without breaking. It might be thought that a iairly high gloss release coating could be achieved by the use oi a release sleeve oi the kind sometimes used for drying cylinders on papermaking or papercoating machines.
It has been iound however that such a sleeve is not satisiactory on a heating roll which has to run in contact with another roll, as the sleeve is dama~ed by the other roll.
Advantageously, the web is pre-heated to a temperature below the so~tening point oi the synthetic thermoplastic material before being heated in a separate heating stage to said temperature above the melting point of the synthetic thermoplastic material.
Pre-heating may ~or example be by means of inra-red i heaters or preferably by hot air heating. Pre-heating has the effect of reducing the temperature gradient through the web when the web is being heated to a temperature above the softening point of the thermoplastic material.
Although the present invention preferably employs heating, transfer and cooling rolls, the web may alternatively be heated and cooled while on the surface of either an endless belt or a single roll.
` Heating may for example be by means o$ in~ra-red heaters or hot air. Cooling may be by cold air, or may be unforced i~ this affords an adequate rate o~
heat loss. An endless belt or single roll is satis$actory if it is desired for long periods to make a web having a particular sur$ace finiæh. However, i$ a variety o$ sur$ace $inishes are to be applied, the three roll system is preferred, since only the cooling roll need be changed.
In order to enable the invention to be more readily understood, re$erence will now be-made to the accompanying drawings, which illustrate diagrammatically and by way o$ example some embodiments thereo$, and in which -Fig. 1 is a schematic side view of a $irst embodiment o$ part o$ a heat consolidation apparatus;
Fig. 2 is a schematic side view o$ an embodiment o$ a heat consolidation apparatus o$ which part is shown in Fig. l;
; Fig. 3 is a partially sectioned partially cut-away view of a heating roll forming part oi the apparatus ' shown in Figs. 1 and 2;
Fig. 4 is a flow diagram of a heating circuit ior the heating roll shown in Fig. 3;
Fig. 5 is a schematic side view oi a second embodiment of part oi a heat consolidation apparatus corresponding to the part shown in Fig. l; and Fig. 6 is a schematic side view o~ a third embodiment o~ part o~ a heat consolidation apparatus corresponding to the part shown in Figs. 1 and 5.
Re~erring iirst to Fig. 1, part oi a heat consolidation apparatus comprises a heating roll 1 having a release coating 2. The release coating i8 pre~erably oi polytetrailuoroethylene, but may alternatively be oi a silicone material or a ceramic material. A rubber covered ~eed roll 8 is mounted to run in contact with the roll 1 to ~orm a low pressure ~0 gulding nip 9 into which a web 10 to be consolidated is fed. The roll 8 need not be positioned so as to de~ine a nip with the roll 1. It may instead be spaced ~rom the roll 1, provided it serves satisiactorily to guide the web on to the suriace o$ the roll 1. The rubber covering on the roll 8 and on other rolls to be described subsequently is shown in this and in other Figures to be described subsequently by hatching around the periphery oi the roll. A rubber covereq transier roll 5 is also G
mounted to run in contact with the roll 1 so as to deiine & nip 6.
106t;~70 The roll 5 is positioned such that the web lO passes round a major proportion of the circumference of the roll l before being transferred.
A cooling roll 3 is mounted to run in contact with the transfer roll 5, so as to define a nip 7 into which the web lO is fed. Further rolls (not shown) are provided to guide the web from the roll 3 after it has passed round slightly more than half the circumference of the roll 3. The surface 4 of the roll 3 is selected in accordance with the æurface characteristics it is desired to impart to the roll. Means (not shown) are provided to pre-heat the web before it reaches the feed ~, roll 8 and heating roll l. The rolls l and 3 are arranged to be positively driven by means (not shown) to lS maintain tension in the web.
In a modification of the apparatus shown in Fig. l, the roll 5 is omitted and the roll 3 runs in contact with the roll l. In use, the web lO is then transferred from the roll l to the roll 3.
Referring now to Fig. 2, there is shown a complete heat consolidation apparatus including the rolls l, 3, 5 and 8 just described with reference to Fig. l. The web lO
is also shown. There is also shown an unwind reel ll on a stand ll a, a pre-heating tunnel generally designated 12, a frame 13 supporting the tunnel l2 and in which the rolls l, 3, S and 8 are journalled (the journals not being shown), and a conventional type oi reel-up assembly comprising a rubber-covered roll 14, and a reel }S supported on an arm 16 J -- g ---` 1066~70 arranged to pivot at 17. The equipment for controlled pivotal movement of the arm 16 and for driving the reel-up assembly is not shown, for the sake of clarity'.
The pre-heating tunnel 12 is divided by a horizontal partition 18 into upper and lower ducts 19 and 20 respectively. A vertical partition 21 depending from the partition 18 defines a vertical duct 22 which connects the ducts 19 and 20. An inlet port 24 is provided for introducing hot air into the duct 19. An outlet port 23 is provided $or exhaust air. Six guide rolls 25 are disposed in the duct 20, so as to define a roughly arcuate path for passage of the web 10 through the tunnel. The web 10 enters and leaves the tunnel through slots (not shown) in the base o~ the tunnel. A duct floor 34 the shape of which generally conforms to the web path is disposed above the rolls 25.
Respective elongate nozzles 35 are directed at the ~olls 25.
Rolls 26, 27 and 28 are provided for guiding the web 10 $rom the reel 11 to the tunnel 12. The rolls 26 and 27 are guide rolls and are journalled in parts oi the ~rame 13 which are not shown for the sake o$
clarity. The roll 28 is a skew roll positioned in a stand 29 and its position in the stand 29 is controllable in conventional manner by a hand wheel 30 to ensure that the web tension is even across the width of the web.
The degree o$ tension in the web is controlled by conventional means (not shown), for example a pneumatic 10~6~70 , or electrical controller? associated with the reel 11 and the roll 27.
Guide rolls 31, 32 and 33 are provided for guiding the web 10 from the roll 3 to the reel-up assembly already described. During this stage, the ~eb lS cooled to around ambient temperature.
In use of the apparatus shown in Figs. 1 and 2, the web 10 is unwound from the reel 11 and the web tension is suitably adjusted. The web is then pre-heated in the tunnel 12, as it passes over the guide rolls 25. Heating is by means of hot air passing through the inlet port 24, along the duct 20, through the nozzle 35 so as to impinge on tbe web, up the duct 22, back along the duct 19 and out through ;
the port 23.
The pre-heated web then passes out of the tunnel 12 and round the feed roll 8 on to the heating roll 1 through the nlp 9. The heating roll is heated internally by means o~ hot oil circulation. A~ter ~0 passage round the roll 1, the temperature of the web -~
is above the softening point oi the synthetic fibres in the web. The so~tened web is then trans~erred to the roll 5, transfer being facilitated by the release coating on the roll 1. While on the roll 5, the web cools slightly, before passing into the nip 7 between the rolls 5 and 3.
The rubber coating on the-roll S prevents the web being subjected to substantial pressure in the nips 6 and 7, and ensures that such pressure as there is i~
- 1066~70 even across the width of the web. It will be appreciated that the nip pressure produced by the rubber coating is much less than would be produced by a steel transfer roll. Whereas a steel roll would be in substantially linear contact with the roll 3, the rubber coating deforms so as to wrap around the roll slightly, so that the force in the nip is spread over a large area, i.e. there is a lower nip pressure. As discussed previously, it is important to avoid high pressure on the web, since it prevents the resultant product having the desired properties.
Although the roll 3 is referred to as a cooling roll, it must be emphasised that the expression "cooling" is used in relation to the temperature of the web arriving at the roll. The cooling roll may still be very hot compared with ambient temperature, but still be cooler than the web, Alternatively, the cooling roll may be maintained at or below ambient temperatures, e.g. by air or water çooling. The temperatures chosen ior the rolls 1 and 3 will be discussed more $ully hereafter.
On the first part oi the cooling roll, the web . i8 still soft. This is important, since the surface of the web in contact with the roll 3 can then "flow"
such that the surface finish of the roll is cast on to the surface oi the ~eb in contact with the roll.
The surface finish may for example be a high gloss finish, a matt finish, or an engraved iinish.
_ 12 1066~70 .
The gentle pressing action of the rubber covered roll 5 in the nip 7 assists the softened web material to flow into close contact with the roll 3, whereby the finish oi' the roll 3 is cast on to the web.
By the time the web leaves the cooling roll, it has cooled to an extent such that it has su~ficient coherence to be unsupported. The coherence is such that there is no need for a release coating on the roll 3, which as discussed previously would prevent the casting o~ a high gloss or engraved i'inish on to the web.
On leaving the roll 3, the web passes over guide rolls 31, 32 and 33 to the reel-up assembly 14, 15, 16.
The temperatures chosen ~or the rolls 1 and 3 depend on the web speed and substance, the diameters o~ the rolls, the proportion o~ the circumi'erence oi the rolls contacted by the web, the extent of pre-heating, and the sur~ace and other characteristics required in - the ~inished product, The heat supplied to the web by the time it leaves the roll 1 should be such that the web is at a temperature slightly above the softening point o~ the thermoplastic material oi which the synthetic ~ibres are made. This normally requires the roll to be considerably hotter than the ~inal web temperature desired. A high roll temperature is needed ~or a fast web speed, ~or a small roll diameter, and ~or a small proportion oi roll suriace in contact with ~; the web. A lower roll temperature will su~ice i~
pre-heating is increased or web substance decreased.
_ 13 1066~70 By way of example, for a 75 g/m2 web made wholly o~
polyethylene ~ibres and travelling at 50 ft/min, with an 8-inch diameter roll, 270 of the circumference a~ which is in contact with the web, a web temperature o~ 180C is suitable.
The web should cool after leaving the roll 1 and while on the roll 3 to a temperature below the softening point oi the thermoplastic material. The rate of heat loss requlred for this depends partly on the substance of the web and partly on the web speed, Ii cooling is too fast, the web may not have time beiore solidiiying t~ adopt closely the finish of the cooling roll. For a low substance web running at low speed, the cooling roll must be fairly hot ii over-cooling is not to occur. For a high substance web running at high speed, the rate o~ heat loss must be greater, and hence the cooling roll must be cooler.
In certain cases, the roll 3 may not need to be heated at all, By way oi example, ior the web described in the pre¢eding paragraph, and whlch has been heated as described in the preceding paragraph, the cooling roll temperature can be in the range 90 to 120C, depending to some extent on the sur~ace finish which it is ~ desired to impart to the web.
The construction o~ the heating roll is important, An oil iilled roll arranged to be heated by electric immersion heaters may be used, However, it is normally t necessary to strengthen such a roll by internal radial metal _ 14 .
webbing. This r.1ay lead to two disadvantages. Firstly, the webbing~being of metal, has a better heat conductivity than the oil, and hence "hot spotsl' are produced on the , sur~ace of the roll opposite the points o~ contact of the webbing and the roll cylinder. Secondly, the webbing may expand and lead to the formation of bumps on the roll surface. It has therefore been found desirable to use a roll construction as will now be described with reference to ~ig. 3, The roll, generally designated 1, comprises a cylinder 40 fitted with end caps 41 and 42. Within the roll 1 is a closed inner drum 43. The roll 1 and the drum 43 are mounted on common trunnions 44 arranged to be mounted in journals (not shown). An axial channel 45, 46 is formed in each trunnion and communicates with the interior o~
the roll 1 through radially disposed channels 47, 48. Two helically disposed fins 49, 50 are mounted on the cylindrical surface o~ the drum 43 to de~ine,two helical races about the drum.
In use, hot oil is pumped in the direction o~ the arrow through the channel 45, ~rom whence it passes into the interior of the roll 1 through the channels 47. The oil then passes along the races defined by the fins 49, 50, - heating the cylinder 40 as it does so. On emerging ~rom the races, the oil passes through the channels 48 and out oi the roll along the channel 46, as indicated by the arrow.
A pre~erred oil ~low and heating circuit will now be described with reference to Fig. 4. By way o~ example, it will be assumed that the heating roll, shown as l in _ 15 1066~7~
Fig. 4, is to be supplied with oil at a temperature oi 180C.
The circuit comprises a heater 60 for heating oil to a temperature considerably greater than is desired for the roll 1, for example 300C and 180C respectively.
A main pump 61 is provided for pumping the heated oil around a closed main circuit 62 and back to heater 60.
A take off pipe 63 leads to a subsidiary circuit 64 for ' heating the roll 1. The subsidiary circuit includes a subsidiary pump 65. A three-way valve 66 is provided at the junction of the pipe 63 and the circuit 64. A
return pipe 67 in which is a one-way valve 68 connects the subsidiary circuit 64 with the main circuit 62. The valve 68 is arranged to permit oil ilow only from the subsidiary circuit 64 to the main circuit 62. An inira-red temperature sensor 69 is provided adjacent the roll 1 to sense its temperature. The sensor is connected to a controller 70 ior the valve 66. The controller may ior example be pneumatically or electrically controlled. The sensing and controlling connections are shown by the dotted lines in Fig. 4.
In use, oil at 300C is pumped continually round the closed circuit 62, as shown by the thick lines in Fig. 4.
When the temperature of the roll drops below 180C, the 26 sensor 69 sends a signal to the controller 70, which in turn causes the valve 66 to open to admit hot oil irom the circuit 62 along the pipe 63, and into the piping 64.
The hot oil is then circulated by the pump 65 through the roll 1, the one-way valve 68, and the piping 67 back to the circuit 62.
- 1066/?t70 When the roll 1 reaches the desired temperature, the sensor 69 signals the controller 70 accordingly.
The valve 66 is then altered to cut off flow o~
hot oil from the pipe 63, and instead to permit circulation of oil at 180C round the closed circuit 64, by means of the pump 65. This is indicated by the thin dashed lines in Fig.4. When the temperature next drops below 180C, the procedure just described is repeated.
I~ precise temperature control o~ the roll 1 is not needed, the subsidiary circuit can be dispersed with, and the roll simply installed in the main circuit. It has been found however that such an arrangement only permits temperature control within about - 3C. The arrangement just described permits control to within about - ~C.
If it is desired to heat the cooling roll 3 to a high temperature, for example 90 to 120C, a iurther ~ubsidiary ¢ircuit can be installed, in parallel with the circuit 64.
The equipment required, and its operation are as described with reference to the circuit 64.
Re~erring now to Fig.5, there is shown an alternative embodiment of the part of the apparatus shown in Fig.l.
The remaining part oi the apparatus is as shown in Fig.2.
The apparatus comprises an endless belt 70 arranged to run around three triangularly disposed rolls 71, 72 and 73.
The roll 71 is a heating roll, and may be as described previously with re~erence to the heating roll 1. A ~eed t roll 74 is provided for guiding a web 10 on to the roll 71 and has the function described previously ~or the roll 8.
_ 17 4'70 A rubber-covered take-o~f roll 75 is provided above the roll 72, and forms a gentle nip with the roll 72. Means (not shown) are provided for pre-heating the web (arrows.
denoted Hl), for pre-heating the belt 70 (arrows denoted H2) and ior cooling the belt (arrows denoted C). The heating means may be infra-red heaters and the cooling means may be cool air jets. Depending on the extent of cooling required, it may be possible to dispense with special cooling means, in that ordinary unforced heat loss from the web may result in adequate temperature loss.
In use, the web 10 passes round the feed roll 74 after having been pre-heated, and on to the surface o~ the belt 70. During passage over the roll 71, the web is heated to a temperature sufficient to ~often the synthetic fibres in the web. The web then passes on the belt to the gentle nip between the rolls 75 and 72 and is then taken oi~ the belt 70. The rolls 74 and 75 together hold the web ~irmly against the belt. The surface iinish of the belt i8 there~ore imparted to the surface o~ the web while the web is in a softened state.
It will be noted that the web remains on the same support, i.e. the beltj throughout the process. There is thus po need for the belt to have a release coating. By ~ the time the web is removed from the belt, the web has cooled sufficiently to have acquir~d sufficient coherence to be pulled from the belt witho~t breaking.
Referring now to Fig.6, there is shown another ,; embodiment of part of a heat consolidation apparatus corresponding to that shown in Fig.l. The remainder of - l066~7b the apparatus is as shown in Fig.2. The apparatus comprises a drivably rotatable roll-80 which is divided internally into compartments 81, 82 by a non-rotatable barrier 83, which makes sealed contact with the inside o~ the roll 80. A rubber-covered feed roll 84, constructed and functioning in the same way as the roll 8, shown in ~ig.l, is provided to guide a web 10 on to the external surface of the roll 80.
A rubber-covered take-of~ roll 85 is provided to guide the web away from the roll 80 after the web has been treated. The rolls 84 and 85 are disposed such that the web contacts a major proportion oi the circumference of the roll 80.
The compartment 82 is arranged to be heated by hot oil. The compartment 81 is arranged to be heated, or cooled, by a suitable fluid, for example oil, steam, water or air. Means (not shown~,e.g. infra-red heaters,may be provided for heating the web externally, (as shown by arrows denoted H). Means (also not shown) e.g. air ~ets, may be provided for cooling the web externally, depending on the extent of cooling required.
In use, the web 10 is pre-heated and passed round the roll 84 onto the surface of the heated part of the drum. The synthetic fibres in the web are thereby soitened.
as On passing beyond the barrier 83, the web is cooled.
While the web is still soft, the surface finish of the roll 80 ls imparted to the web, since the web is held firmly against the-roll by means oi the rolls 84 and 85.
` 106~4~70 After cooling, the web is guided away ~rom the roll 80 by the roll 85.
Since the web is on the surface of the roll 80 ; throughout the process, there is no need for the roll 80 to carry a release coating. This is because by the time the web is taken off the roll 80, it has cooled to an extent adequate to give the web the necessary coherence to prevent breaking of the web.
It may not be necessary for the web to be heated both from within and without the roll. Only heating from within or only heating from without may be used if sufficient heat can be supplied to the web in that way.
If it is desired to impart particular surface finsihes to both surfaces of the web, two sets of apparatus as described herein may be used, positioned in line so as to treat first one surface and then the other. Alternatively, the one apparatus may contain me~ns ior heating and surface finishing the web iirst on one side and then on the other. It is also possible to suriace iinish both sides simultaneously between two cooling rolls, provided these are mounted so as not to apply substantial pressure to the web.
Paper webs have traditionally been formed from cellulosic fibre derived from various material of vegetable origin, for example woodpulp. More recently proposals have been made for the production of so-called synthetic wood pulp fibres from various polymeræ. Such fibres have a gross morphology, ie. length:diameter ratio, and diameter of the same order of magnitude as cellulosic papermaking fibres derived from woodpulp. They are distinguished from most synthetic textile fibres by their gross morphology and diameter.
The use of synthetic fibres in papermaking affords the possibility of producing webs with novel properties.
One such possibility, provided the synthetic fibres are of a thermoplastic material, is that of heat treatment to soften the fibres, and thereby to produce a partially or wholly consolidated sheet.
It is an object of the invention to provide an improved method for heat treatment of a web of intermeshed fibres at least a proportion of which are of a synthetic thermoplastic material.
According to a first aspect of the invention, there is provided a method of continuously consolidating and surface finishing a paper web substantially all the fibres of which are of a synthetic thermoplastic material, com-prising the steps of heating the web to a temperature above the softening point of the synthetic thermoplastic material, B
the web being supported throughout the time it is above the softening point of the thermoplastic material, and sub-sequently cooling the web from a temperature above the softening point of the synthetic thermoplastic material to a temperature below the softening point of the thermoplastic material while the web is in contact with a forming surface, so that the finish of the forming surface is imparted to the surface of the web without subjecting the web to substantial pressure during the time it is so supported.
In a further aspect the invention is a consoli-dated surface finished web produced by the above method.
It will be appreciated that the present method consolidates the web by the action of heat rather than pressure, as is discussed more fully hereafter.
,~
Preferably, the web is heated by passage round part of the circumference of a heating roll. The roll may be heated for example by hot oil or steam, but the former is preferred as steam presents more S problems o~ pressure sealing.
Preferably, the web is cooled by passage round part of the circumference of a cooling roll, the surface of which constitutes said forming sur$ace.
The cooling roll may be at a temperature below the soitening point of the thermoplastic material of which the fibres are made, but still considerably in excess oi ambient temperature, or it may be at or below ambient temperature. If the cooling roll is to be chilled, air or cold water may be used. The choice of temperature ~or the cooling roll depends largely on the nature of the web and on process parameters, as will be discussed more fully hereafter.
The cooling roll finish, which is imparted to the web, may take various ~orms. For example, it may be a high gloss ~inish, a matt ~inish, obtained ~or example by shot-blasting, or an engraved ~inish.
Advantageously, the web is transferred ~rom the heating roll to the cooling roll by means of a trans~er roll running in contact with both the heating and cooling 2S rolls. Tbe transier roll has a resilient covering, for example of rubber, so that in passing between a nip formed by the transfer and cooling rolls, the roll will not be subjected to heavy pressure which prevents the 106~i~70 achievement of the desired web properties. Although the resilient surface of the transfer roll gently presses the web against the surface of the cooling roll, the pressure is much less than that used in conventional hot pressing processes. As a result of the gentle pressing of the web against the surface of the cooling roll, imparting of the surface finish ~ oi the cooling roll to the web is facilitated. The ; way in which the surface finish is imparted to the web is analogous to a casting process, in that the softened thermoplastic material "flows" and thereby accurately adopts the finish of the supporting surface.
, Once the web has been heated to a temperature above the softening point of the thermoplastic material of which the fibres are made, the web has little coherence. Consequently, it is necessary for the web to be supported until it is again at a temperature some way below the softening point. I~ the web were unsupported when above or very near the softening 20 ~ point, it would be likely to break, stretch or be otherwise deformed.
The coherence o$ the softened web depends to some extent on the extent of consolidation required in the finished web, and on whether it contains a proportion of non-thermoplastic fibres, e.g. cellulosic fibres.
If only partial consolidation is being carried out, or coherence ie imparted by the presence o~ non-thermoplastic fibres, it may be possible to support the web on air jets.
~ - 5 - Otherwise, a supporting member or members is required.
The type of support which will su~fice wilI be readily apparent to the skilled worker in the ar~.
A ~urther consequence o~ the lack of coherence oi the softened web is that if the web is to be transferred from one support member to another while in a soit state, the support member from which the web is being transferred must be treated to facilitate release of the web. Desirably this is achieved by means of a release coating, preferably o~ polytetra-i'luoroethylene. A problem associated with release coatings for use in the present method and apparatus i8 that they cannot have a high gloss i'inish or an engraved ~inish,so i'ar as is known at present. Hence in order to achieve such a finish, the web must be transferred while still soi't to a supporting sur~ace having the desired finish, and on which the web is cooled to a temperature at which it has the coherence necessary to be drawn of~ the supporting suriace without breaking. It might be thought that a iairly high gloss release coating could be achieved by the use oi a release sleeve oi the kind sometimes used for drying cylinders on papermaking or papercoating machines.
It has been iound however that such a sleeve is not satisiactory on a heating roll which has to run in contact with another roll, as the sleeve is dama~ed by the other roll.
Advantageously, the web is pre-heated to a temperature below the so~tening point oi the synthetic thermoplastic material before being heated in a separate heating stage to said temperature above the melting point of the synthetic thermoplastic material.
Pre-heating may ~or example be by means of inra-red i heaters or preferably by hot air heating. Pre-heating has the effect of reducing the temperature gradient through the web when the web is being heated to a temperature above the softening point of the thermoplastic material.
Although the present invention preferably employs heating, transfer and cooling rolls, the web may alternatively be heated and cooled while on the surface of either an endless belt or a single roll.
` Heating may for example be by means o$ in~ra-red heaters or hot air. Cooling may be by cold air, or may be unforced i~ this affords an adequate rate o~
heat loss. An endless belt or single roll is satis$actory if it is desired for long periods to make a web having a particular sur$ace finiæh. However, i$ a variety o$ sur$ace $inishes are to be applied, the three roll system is preferred, since only the cooling roll need be changed.
In order to enable the invention to be more readily understood, re$erence will now be-made to the accompanying drawings, which illustrate diagrammatically and by way o$ example some embodiments thereo$, and in which -Fig. 1 is a schematic side view of a $irst embodiment o$ part o$ a heat consolidation apparatus;
Fig. 2 is a schematic side view o$ an embodiment o$ a heat consolidation apparatus o$ which part is shown in Fig. l;
; Fig. 3 is a partially sectioned partially cut-away view of a heating roll forming part oi the apparatus ' shown in Figs. 1 and 2;
Fig. 4 is a flow diagram of a heating circuit ior the heating roll shown in Fig. 3;
Fig. 5 is a schematic side view oi a second embodiment of part oi a heat consolidation apparatus corresponding to the part shown in Fig. l; and Fig. 6 is a schematic side view o~ a third embodiment o~ part o~ a heat consolidation apparatus corresponding to the part shown in Figs. 1 and 5.
Re~erring iirst to Fig. 1, part oi a heat consolidation apparatus comprises a heating roll 1 having a release coating 2. The release coating i8 pre~erably oi polytetrailuoroethylene, but may alternatively be oi a silicone material or a ceramic material. A rubber covered ~eed roll 8 is mounted to run in contact with the roll 1 to ~orm a low pressure ~0 gulding nip 9 into which a web 10 to be consolidated is fed. The roll 8 need not be positioned so as to de~ine a nip with the roll 1. It may instead be spaced ~rom the roll 1, provided it serves satisiactorily to guide the web on to the suriace o$ the roll 1. The rubber covering on the roll 8 and on other rolls to be described subsequently is shown in this and in other Figures to be described subsequently by hatching around the periphery oi the roll. A rubber covereq transier roll 5 is also G
mounted to run in contact with the roll 1 so as to deiine & nip 6.
106t;~70 The roll 5 is positioned such that the web lO passes round a major proportion of the circumference of the roll l before being transferred.
A cooling roll 3 is mounted to run in contact with the transfer roll 5, so as to define a nip 7 into which the web lO is fed. Further rolls (not shown) are provided to guide the web from the roll 3 after it has passed round slightly more than half the circumference of the roll 3. The surface 4 of the roll 3 is selected in accordance with the æurface characteristics it is desired to impart to the roll. Means (not shown) are provided to pre-heat the web before it reaches the feed ~, roll 8 and heating roll l. The rolls l and 3 are arranged to be positively driven by means (not shown) to lS maintain tension in the web.
In a modification of the apparatus shown in Fig. l, the roll 5 is omitted and the roll 3 runs in contact with the roll l. In use, the web lO is then transferred from the roll l to the roll 3.
Referring now to Fig. 2, there is shown a complete heat consolidation apparatus including the rolls l, 3, 5 and 8 just described with reference to Fig. l. The web lO
is also shown. There is also shown an unwind reel ll on a stand ll a, a pre-heating tunnel generally designated 12, a frame 13 supporting the tunnel l2 and in which the rolls l, 3, S and 8 are journalled (the journals not being shown), and a conventional type oi reel-up assembly comprising a rubber-covered roll 14, and a reel }S supported on an arm 16 J -- g ---` 1066~70 arranged to pivot at 17. The equipment for controlled pivotal movement of the arm 16 and for driving the reel-up assembly is not shown, for the sake of clarity'.
The pre-heating tunnel 12 is divided by a horizontal partition 18 into upper and lower ducts 19 and 20 respectively. A vertical partition 21 depending from the partition 18 defines a vertical duct 22 which connects the ducts 19 and 20. An inlet port 24 is provided for introducing hot air into the duct 19. An outlet port 23 is provided $or exhaust air. Six guide rolls 25 are disposed in the duct 20, so as to define a roughly arcuate path for passage of the web 10 through the tunnel. The web 10 enters and leaves the tunnel through slots (not shown) in the base o~ the tunnel. A duct floor 34 the shape of which generally conforms to the web path is disposed above the rolls 25.
Respective elongate nozzles 35 are directed at the ~olls 25.
Rolls 26, 27 and 28 are provided for guiding the web 10 $rom the reel 11 to the tunnel 12. The rolls 26 and 27 are guide rolls and are journalled in parts oi the ~rame 13 which are not shown for the sake o$
clarity. The roll 28 is a skew roll positioned in a stand 29 and its position in the stand 29 is controllable in conventional manner by a hand wheel 30 to ensure that the web tension is even across the width of the web.
The degree o$ tension in the web is controlled by conventional means (not shown), for example a pneumatic 10~6~70 , or electrical controller? associated with the reel 11 and the roll 27.
Guide rolls 31, 32 and 33 are provided for guiding the web 10 from the roll 3 to the reel-up assembly already described. During this stage, the ~eb lS cooled to around ambient temperature.
In use of the apparatus shown in Figs. 1 and 2, the web 10 is unwound from the reel 11 and the web tension is suitably adjusted. The web is then pre-heated in the tunnel 12, as it passes over the guide rolls 25. Heating is by means of hot air passing through the inlet port 24, along the duct 20, through the nozzle 35 so as to impinge on tbe web, up the duct 22, back along the duct 19 and out through ;
the port 23.
The pre-heated web then passes out of the tunnel 12 and round the feed roll 8 on to the heating roll 1 through the nlp 9. The heating roll is heated internally by means o~ hot oil circulation. A~ter ~0 passage round the roll 1, the temperature of the web -~
is above the softening point oi the synthetic fibres in the web. The so~tened web is then trans~erred to the roll 5, transfer being facilitated by the release coating on the roll 1. While on the roll 5, the web cools slightly, before passing into the nip 7 between the rolls 5 and 3.
The rubber coating on the-roll S prevents the web being subjected to substantial pressure in the nips 6 and 7, and ensures that such pressure as there is i~
- 1066~70 even across the width of the web. It will be appreciated that the nip pressure produced by the rubber coating is much less than would be produced by a steel transfer roll. Whereas a steel roll would be in substantially linear contact with the roll 3, the rubber coating deforms so as to wrap around the roll slightly, so that the force in the nip is spread over a large area, i.e. there is a lower nip pressure. As discussed previously, it is important to avoid high pressure on the web, since it prevents the resultant product having the desired properties.
Although the roll 3 is referred to as a cooling roll, it must be emphasised that the expression "cooling" is used in relation to the temperature of the web arriving at the roll. The cooling roll may still be very hot compared with ambient temperature, but still be cooler than the web, Alternatively, the cooling roll may be maintained at or below ambient temperatures, e.g. by air or water çooling. The temperatures chosen ior the rolls 1 and 3 will be discussed more $ully hereafter.
On the first part oi the cooling roll, the web . i8 still soft. This is important, since the surface of the web in contact with the roll 3 can then "flow"
such that the surface finish of the roll is cast on to the surface oi the ~eb in contact with the roll.
The surface finish may for example be a high gloss finish, a matt finish, or an engraved iinish.
_ 12 1066~70 .
The gentle pressing action of the rubber covered roll 5 in the nip 7 assists the softened web material to flow into close contact with the roll 3, whereby the finish oi' the roll 3 is cast on to the web.
By the time the web leaves the cooling roll, it has cooled to an extent such that it has su~ficient coherence to be unsupported. The coherence is such that there is no need for a release coating on the roll 3, which as discussed previously would prevent the casting o~ a high gloss or engraved i'inish on to the web.
On leaving the roll 3, the web passes over guide rolls 31, 32 and 33 to the reel-up assembly 14, 15, 16.
The temperatures chosen ~or the rolls 1 and 3 depend on the web speed and substance, the diameters o~ the rolls, the proportion o~ the circumi'erence oi the rolls contacted by the web, the extent of pre-heating, and the sur~ace and other characteristics required in - the ~inished product, The heat supplied to the web by the time it leaves the roll 1 should be such that the web is at a temperature slightly above the softening point o~ the thermoplastic material oi which the synthetic ~ibres are made. This normally requires the roll to be considerably hotter than the ~inal web temperature desired. A high roll temperature is needed ~or a fast web speed, ~or a small roll diameter, and ~or a small proportion oi roll suriace in contact with ~; the web. A lower roll temperature will su~ice i~
pre-heating is increased or web substance decreased.
_ 13 1066~70 By way of example, for a 75 g/m2 web made wholly o~
polyethylene ~ibres and travelling at 50 ft/min, with an 8-inch diameter roll, 270 of the circumference a~ which is in contact with the web, a web temperature o~ 180C is suitable.
The web should cool after leaving the roll 1 and while on the roll 3 to a temperature below the softening point oi the thermoplastic material. The rate of heat loss requlred for this depends partly on the substance of the web and partly on the web speed, Ii cooling is too fast, the web may not have time beiore solidiiying t~ adopt closely the finish of the cooling roll. For a low substance web running at low speed, the cooling roll must be fairly hot ii over-cooling is not to occur. For a high substance web running at high speed, the rate o~ heat loss must be greater, and hence the cooling roll must be cooler.
In certain cases, the roll 3 may not need to be heated at all, By way oi example, ior the web described in the pre¢eding paragraph, and whlch has been heated as described in the preceding paragraph, the cooling roll temperature can be in the range 90 to 120C, depending to some extent on the sur~ace finish which it is ~ desired to impart to the web.
The construction o~ the heating roll is important, An oil iilled roll arranged to be heated by electric immersion heaters may be used, However, it is normally t necessary to strengthen such a roll by internal radial metal _ 14 .
webbing. This r.1ay lead to two disadvantages. Firstly, the webbing~being of metal, has a better heat conductivity than the oil, and hence "hot spotsl' are produced on the , sur~ace of the roll opposite the points o~ contact of the webbing and the roll cylinder. Secondly, the webbing may expand and lead to the formation of bumps on the roll surface. It has therefore been found desirable to use a roll construction as will now be described with reference to ~ig. 3, The roll, generally designated 1, comprises a cylinder 40 fitted with end caps 41 and 42. Within the roll 1 is a closed inner drum 43. The roll 1 and the drum 43 are mounted on common trunnions 44 arranged to be mounted in journals (not shown). An axial channel 45, 46 is formed in each trunnion and communicates with the interior o~
the roll 1 through radially disposed channels 47, 48. Two helically disposed fins 49, 50 are mounted on the cylindrical surface o~ the drum 43 to de~ine,two helical races about the drum.
In use, hot oil is pumped in the direction o~ the arrow through the channel 45, ~rom whence it passes into the interior of the roll 1 through the channels 47. The oil then passes along the races defined by the fins 49, 50, - heating the cylinder 40 as it does so. On emerging ~rom the races, the oil passes through the channels 48 and out oi the roll along the channel 46, as indicated by the arrow.
A pre~erred oil ~low and heating circuit will now be described with reference to Fig. 4. By way o~ example, it will be assumed that the heating roll, shown as l in _ 15 1066~7~
Fig. 4, is to be supplied with oil at a temperature oi 180C.
The circuit comprises a heater 60 for heating oil to a temperature considerably greater than is desired for the roll 1, for example 300C and 180C respectively.
A main pump 61 is provided for pumping the heated oil around a closed main circuit 62 and back to heater 60.
A take off pipe 63 leads to a subsidiary circuit 64 for ' heating the roll 1. The subsidiary circuit includes a subsidiary pump 65. A three-way valve 66 is provided at the junction of the pipe 63 and the circuit 64. A
return pipe 67 in which is a one-way valve 68 connects the subsidiary circuit 64 with the main circuit 62. The valve 68 is arranged to permit oil ilow only from the subsidiary circuit 64 to the main circuit 62. An inira-red temperature sensor 69 is provided adjacent the roll 1 to sense its temperature. The sensor is connected to a controller 70 ior the valve 66. The controller may ior example be pneumatically or electrically controlled. The sensing and controlling connections are shown by the dotted lines in Fig. 4.
In use, oil at 300C is pumped continually round the closed circuit 62, as shown by the thick lines in Fig. 4.
When the temperature of the roll drops below 180C, the 26 sensor 69 sends a signal to the controller 70, which in turn causes the valve 66 to open to admit hot oil irom the circuit 62 along the pipe 63, and into the piping 64.
The hot oil is then circulated by the pump 65 through the roll 1, the one-way valve 68, and the piping 67 back to the circuit 62.
- 1066/?t70 When the roll 1 reaches the desired temperature, the sensor 69 signals the controller 70 accordingly.
The valve 66 is then altered to cut off flow o~
hot oil from the pipe 63, and instead to permit circulation of oil at 180C round the closed circuit 64, by means of the pump 65. This is indicated by the thin dashed lines in Fig.4. When the temperature next drops below 180C, the procedure just described is repeated.
I~ precise temperature control o~ the roll 1 is not needed, the subsidiary circuit can be dispersed with, and the roll simply installed in the main circuit. It has been found however that such an arrangement only permits temperature control within about - 3C. The arrangement just described permits control to within about - ~C.
If it is desired to heat the cooling roll 3 to a high temperature, for example 90 to 120C, a iurther ~ubsidiary ¢ircuit can be installed, in parallel with the circuit 64.
The equipment required, and its operation are as described with reference to the circuit 64.
Re~erring now to Fig.5, there is shown an alternative embodiment of the part of the apparatus shown in Fig.l.
The remaining part oi the apparatus is as shown in Fig.2.
The apparatus comprises an endless belt 70 arranged to run around three triangularly disposed rolls 71, 72 and 73.
The roll 71 is a heating roll, and may be as described previously with re~erence to the heating roll 1. A ~eed t roll 74 is provided for guiding a web 10 on to the roll 71 and has the function described previously ~or the roll 8.
_ 17 4'70 A rubber-covered take-o~f roll 75 is provided above the roll 72, and forms a gentle nip with the roll 72. Means (not shown) are provided for pre-heating the web (arrows.
denoted Hl), for pre-heating the belt 70 (arrows denoted H2) and ior cooling the belt (arrows denoted C). The heating means may be infra-red heaters and the cooling means may be cool air jets. Depending on the extent of cooling required, it may be possible to dispense with special cooling means, in that ordinary unforced heat loss from the web may result in adequate temperature loss.
In use, the web 10 passes round the feed roll 74 after having been pre-heated, and on to the surface o~ the belt 70. During passage over the roll 71, the web is heated to a temperature sufficient to ~often the synthetic fibres in the web. The web then passes on the belt to the gentle nip between the rolls 75 and 72 and is then taken oi~ the belt 70. The rolls 74 and 75 together hold the web ~irmly against the belt. The surface iinish of the belt i8 there~ore imparted to the surface o~ the web while the web is in a softened state.
It will be noted that the web remains on the same support, i.e. the beltj throughout the process. There is thus po need for the belt to have a release coating. By ~ the time the web is removed from the belt, the web has cooled sufficiently to have acquir~d sufficient coherence to be pulled from the belt witho~t breaking.
Referring now to Fig.6, there is shown another ,; embodiment of part of a heat consolidation apparatus corresponding to that shown in Fig.l. The remainder of - l066~7b the apparatus is as shown in Fig.2. The apparatus comprises a drivably rotatable roll-80 which is divided internally into compartments 81, 82 by a non-rotatable barrier 83, which makes sealed contact with the inside o~ the roll 80. A rubber-covered feed roll 84, constructed and functioning in the same way as the roll 8, shown in ~ig.l, is provided to guide a web 10 on to the external surface of the roll 80.
A rubber-covered take-of~ roll 85 is provided to guide the web away from the roll 80 after the web has been treated. The rolls 84 and 85 are disposed such that the web contacts a major proportion oi the circumference of the roll 80.
The compartment 82 is arranged to be heated by hot oil. The compartment 81 is arranged to be heated, or cooled, by a suitable fluid, for example oil, steam, water or air. Means (not shown~,e.g. infra-red heaters,may be provided for heating the web externally, (as shown by arrows denoted H). Means (also not shown) e.g. air ~ets, may be provided for cooling the web externally, depending on the extent of cooling required.
In use, the web 10 is pre-heated and passed round the roll 84 onto the surface of the heated part of the drum. The synthetic fibres in the web are thereby soitened.
as On passing beyond the barrier 83, the web is cooled.
While the web is still soft, the surface finish of the roll 80 ls imparted to the web, since the web is held firmly against the-roll by means oi the rolls 84 and 85.
` 106~4~70 After cooling, the web is guided away ~rom the roll 80 by the roll 85.
Since the web is on the surface of the roll 80 ; throughout the process, there is no need for the roll 80 to carry a release coating. This is because by the time the web is taken off the roll 80, it has cooled to an extent adequate to give the web the necessary coherence to prevent breaking of the web.
It may not be necessary for the web to be heated both from within and without the roll. Only heating from within or only heating from without may be used if sufficient heat can be supplied to the web in that way.
If it is desired to impart particular surface finsihes to both surfaces of the web, two sets of apparatus as described herein may be used, positioned in line so as to treat first one surface and then the other. Alternatively, the one apparatus may contain me~ns ior heating and surface finishing the web iirst on one side and then on the other. It is also possible to suriace iinish both sides simultaneously between two cooling rolls, provided these are mounted so as not to apply substantial pressure to the web.
Claims (10)
1. A method of continuously consolidating and surface finishing a paper web substantially all the fibres of which are of a synthetic thermoplastic material, com-prising the steps of heating the web to a temperature above the softening point of the synthetic thermoplastic material, the web being supported throughout the time it is above the softening point of the thermoplastic material, and sub-sequently cooling the web from a temperature above the softening point of the synthetic thermoplastic material to a temperature below the softening point of the thermoplastic material while the web is in contact with a forming surface, so that the finish of the forming surface is imparted to the surface of the web without subjecting the web to substantial pressure during the time it is so supported.
2. A method as claimed in claim 1, wherein the web is heated by passage round part of the circumference of a heating roll.
3. A method as claimed in claim 1 wherein the web is cooled by passage round part of the circumference of a cooling roll the surface of which constitutes said forming surface.
4. A method as claimed in claims 2 and 3 wherein the web is transferred from the heating roll to the cooling roll by passage round part of the circumference of a trans-fer roll having a resilient covering, the transfer roll running in contact with both the heating and cooling rolls and defining a nip with the cooling roll serving to press the web gently against the surface of the cooling roll while the web is still soft, whereby the surface finish of the cooling roll is imparted to the web.
5. A method as claimed in claim 3 wherein the cooling roll is at a temperature slightly below the soften-ing point of the thermoplastic material of which the fibres are made but which is considerably in excess of ambient temperature.
6. A method as claimed in claim 3 wherein the cooling roll is at or near ambient temperature.
7. A method as claimed in claim 1 wherein the web is heated and cooled while on the surface of an endless belt.
8. A method as claimed in claim 1 wherein the web is heated and cooled while on the surface of a single roll.
9. A method as claimed in any one of claims 1 to 3 wherein the web is pre-heated to a temperature below the softening point of the synthetic thermoplastic material before being heated in a separate heating stage to said temperature above the softening point of the synthetic thermoplastic material.
10. A consolidated surface finished web produced by a method as claimed in any one of claims 1 to 3.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB142275A GB1540056A (en) | 1975-01-13 | 1975-01-13 | Heat treatment of a web containing fibres of thermoplastic material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1066470A true CA1066470A (en) | 1979-11-20 |
Family
ID=9721751
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA243,119A Expired CA1066470A (en) | 1975-01-13 | 1976-01-07 | Equipment for use in the manufacture of web material |
Country Status (17)
| Country | Link |
|---|---|
| JP (1) | JPS609160B2 (en) |
| AR (1) | AR209466A1 (en) |
| BE (1) | BE837511A (en) |
| BR (1) | BR7600153A (en) |
| CA (1) | CA1066470A (en) |
| CH (1) | CH606611A5 (en) |
| DE (1) | DE2600596A1 (en) |
| DK (1) | DK8976A (en) |
| ES (1) | ES444206A1 (en) |
| FI (1) | FI760056A (en) |
| FR (1) | FR2297271A1 (en) |
| GB (1) | GB1540056A (en) |
| IE (1) | IE41985B1 (en) |
| IT (1) | IT1054772B (en) |
| LU (1) | LU74153A1 (en) |
| NL (1) | NL7600199A (en) |
| SE (1) | SE428136B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1603830A (en) * | 1977-11-10 | 1981-12-02 | Wiggins Teape Group Ltd | Photographic support |
| JPS5668150A (en) * | 1979-11-06 | 1981-06-08 | Seikichi Kashiyama | Production of press felt |
| JPS56118972A (en) * | 1980-02-20 | 1981-09-18 | Chubu Kakou Kk | Production of interior material |
| US4568596A (en) * | 1984-07-18 | 1986-02-04 | Hercules Incorporated | Nonwoven fabric |
| JPS62203285U (en) * | 1986-06-14 | 1987-12-25 | ||
| DE4126233C1 (en) * | 1991-08-08 | 1992-09-17 | Sulzer-Escher Wyss Gmbh, 7980 Ravensburg, De | |
| GB9521276D0 (en) * | 1995-10-18 | 1995-12-20 | Wiggins Teape Group The Limite | Casting paper |
| DE19813341A1 (en) * | 1998-03-26 | 1999-09-30 | Truetzschler Gmbh & Co Kg | Carding machine device for production of a fiber web |
| FI119822B (en) | 2000-11-21 | 2009-03-31 | Metso Paper Inc | Method and apparatus for introducing a web into a paper or board machine finishing device |
| DE10157686B4 (en) * | 2001-11-24 | 2005-11-17 | Voith Paper Patent Gmbh | Calender and method for smoothing a paper or board web |
| US7514030B2 (en) | 2002-12-30 | 2009-04-07 | Albany International Corp. | Fabric characteristics by flat calendering |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2140866C3 (en) * | 1971-08-14 | 1978-12-21 | Bayer Ag, 5090 Leverkusen | Tetrakisazo dyes and their use for dyeing leather |
| US3712266A (en) * | 1971-08-20 | 1973-01-23 | Ibm | Developer conveying apparatus |
-
1975
- 1975-01-13 GB GB142275A patent/GB1540056A/en not_active Expired
- 1975-12-30 IE IE283175A patent/IE41985B1/en unknown
-
1976
- 1976-01-07 CA CA243,119A patent/CA1066470A/en not_active Expired
- 1976-01-08 SE SE7600136A patent/SE428136B/en not_active IP Right Cessation
- 1976-01-09 DE DE19762600596 patent/DE2600596A1/en not_active Ceased
- 1976-01-09 FR FR7600463A patent/FR2297271A1/en active Granted
- 1976-01-09 LU LU74153A patent/LU74153A1/xx unknown
- 1976-01-09 NL NL7600199A patent/NL7600199A/en not_active Application Discontinuation
- 1976-01-10 ES ES444206A patent/ES444206A1/en not_active Expired
- 1976-01-12 FI FI760056A patent/FI760056A/fi not_active Application Discontinuation
- 1976-01-12 DK DK8976A patent/DK8976A/en unknown
- 1976-01-12 IT IT1916576A patent/IT1054772B/en active
- 1976-01-12 BR BR7600153A patent/BR7600153A/en unknown
- 1976-01-13 BE BE163469A patent/BE837511A/en unknown
- 1976-01-13 CH CH31776A patent/CH606611A5/xx not_active IP Right Cessation
- 1976-01-13 AR AR26181776A patent/AR209466A1/en active
- 1976-01-13 JP JP51003717A patent/JPS609160B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| CH606611A5 (en) | 1978-11-15 |
| JPS5196579A (en) | 1976-08-24 |
| SE7600136L (en) | 1976-07-14 |
| FI760056A (en) | 1976-07-14 |
| DE2600596A1 (en) | 1976-07-15 |
| ES444206A1 (en) | 1977-05-01 |
| IE41985L (en) | 1976-07-13 |
| LU74153A1 (en) | 1976-07-20 |
| IT1054772B (en) | 1981-11-30 |
| BR7600153A (en) | 1976-11-09 |
| SE428136B (en) | 1983-06-06 |
| NL7600199A (en) | 1976-07-15 |
| AR209466A1 (en) | 1977-04-29 |
| FR2297271A1 (en) | 1976-08-06 |
| GB1540056A (en) | 1979-02-07 |
| FR2297271B1 (en) | 1981-12-31 |
| DK8976A (en) | 1976-07-14 |
| JPS609160B2 (en) | 1985-03-08 |
| IE41985B1 (en) | 1980-05-07 |
| BE837511A (en) | 1976-05-03 |
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