GB2045163A - Compressible press packing containing non-compressible thermosol lamina - Google Patents

Abstract

A compressible press-packing laminate is provided comprising a preferably highly porous compressible lamina and a lamina which is a solid non-compressible heat-set composition, generally derived from a polyvinyl polymer plastisol, a crosslinkable polyacrylate and optionally a phenolic resin. The invention also provides a process for manufacturing such a laminate which comprises applying a coating of the plastisol at least 2 mils (0.05 mm) thick onto a compressible lamina, solidifying said coating, thereafter, in a second step, curing said coating. A typical laminate is shown in Figure 1. <IMAGE>

Description

SPECIFICATION Compressible press packing containing non-compressible thermosol lamina The invention relates to a resilient compressible element having at least two lamina, one of which is a compressible layer, usable as a printing element.

It is an object of the present invention to provide an improved printers packing that will outperform known packings and, in particular, have as few disadvantages as possible, for example substantially eliminating pollution, reducing cost, and conserving energy as well as increase the productivity of labour, manufacturing equipment and space.

To give some disadvantages inherent in prior procedures usedin producing printing elements, solvent laid elastomers generally require a number of coating passes or a number of in-line coatings to enable the expeditious removal of the solvent. Elastomers applied by milling have the disadvantage of poor adhesion, trapping air and difficult caliper control. While plastisols are not known to have been used to produce resilient compressible printing elements they would have the obvious disadvantage of being subject to heat deformation, poor solvent resistance and poor impact resistance.It might be thought that thermosols would also have disadvantages such as instability of solution viscosity and likely precuring prior to good lamination, but it has surprisingly been found according to the present invention that the thermosols are not only easily coated on to the desired compressible lamina but the thermosols can be formed into sufficiently resilient lamina with sufficient integrity to give improved resistance to collapse over long usage compared to the laminate structures of the prior art.

Accordingly the present invention provides a resilient compressible press-packing laminate comprising a compressible lamina and a lamina which is a solid non-compressible heat-set composition, preferably a thermosol lamina. Preferably the compressible lamina contains voids and is a fibrous sheet impregnated with an epoxy resin. The voids preferably comprise at least about 20% of the volume of the compressible lamina. The thermosol is preferably a polyvinyl plastisol with a cross-linkable monomer which is a polyacrylate. Other laminas ofthermosol and compressible material and laminas of woven textile may be added. A thermosol lamina may form an outer working face for the resilient compressible printing element in some preferred constructions.

Any material that will cross-link with the polyvinyl polymer of the plastisol to form a thermoset polymer may be used. Further the thermosol can in some instances be replaced by what at present is considered a less desirable flexible material so long as the tensile stress is at least about 800 psi (55 kg/cm2), preferably at least about 1000 psi (70 kg/cm2).

The present invention also provides a thermosol (i.e. thermosetting plastisol) composition which comprises about 30 to about 95% by weight polyvinyl polymer-containing plastisol, about 2 to about 20% by weight polyacrylate monomer cross-linkable with said polyvinyl polymer to form a thermoset polymer, and about 2 to about 30% by weight phenolic resin. The thermosol preferably includes a peroxide free-radical initiator. The polyvinyl plastisol polymer is preferably a polyvinyl chloride and the acrylate monomer is preferably a di- ortri-acrylate. The plastisol's plasticizer is preferably dioctyl phthalate present in an amount of about 15 to about 65% by weight of the plastisol.

Thermosol materials using polyvinyl chloride plastisol together with the cross-linking monomers 1,3-butylene dimethacrylate and trimethylolpropane trimethacrylate are shown in the sales brochure of Rohm and Hass Company, CM-32.

The highly porous compressible lamina is preferably at least 10 mils (0.25 mm) thick and the thermosol lamina is preferably at least 2 mils (0.05 mm) thick.

The present invention also provides a process for manufacturing a resilient compressible press-packing laminate which involves simply coating a liquid thermosol coating at least 2 mils (0.05 mm) thick onto a lamina, solidifying the thermosol coating throughout, plying a second lamina over the solidified thermosol coating, and activating the thermosol coating to adhere the laminas together and thermoset the thermosol.

The solidifying is preferably accomplished by heating to cause gelling and said thermosetting is by heating to a higher temperature. The preferred thermosol is the one described above.

The thermosol composition of the present invention comprises about 30 to about 95% by weight polyvinyl polymer-containing plastisol, more preferably about 70 to about 90% and most preferably about 75 to about 85% by weight. The polyvinyl polymer is preferably polyvinyl chloride and the plasticizer is preferably dioctyl phthalate present in an amount of about 1 5to about 65%, more preferably about 25 to about 55% by weight of the plastisol. The composition also contains an acrylate monomer cross-linkable with the polyvinyl polymer to form the thermoset polymer.The acrylate monomer is preferably a di- or tri-acrylate, especially trimethylolpropane trimethacrylate, and is preferably present in an amount of about 2 to about 20%, more preferably about 3 to about 10% and most preferably about 5 to about 2%, by weight of the total composition. The thermosol composition preferably includes a peroxide free-radical initiator, preferably a peroxyketal, preferably present in an amount of .01 to 1% by weight.

An important component, and in its preferred form, a critical ingredient of the thermosol composition is a phenolic resin. The phenolic resin is preferably present in an amount of about 2 to about 30%, more preferably about 8 to about 15% and most preferably about 11 to about 13%, by weight. The phenolic resin is preferably of the thermosetting two-step type. When the phenolic resin is present the composition is, in its thermoset condition, stiffer but still very resilient and flexible and the composition provides better characteristics as a press packing work surface or interlay lamina over plys of resilient compressible material, particularly those made from highly porous fibrous material.

The thermosol composition can also, of course, contain other ingredients such as stabilizers, fillers and pigmenting agents.

The present invention will now be described, merely by way of illustration, with reference to the accompanying drawings in which: Figure lisa diagrammatic cross section view of a resilient compressible printing element laminate of the present invention labelled to assist easy following of the description.

Figure 2 is a schematic diagram of a preferred method for preparing the element.

The labelling in Figure 1 is particularly designed to show the basic structure and indicate additional laminas that may be added to expand the usefulness of the present invention. The order of the laminas, Ist, 2nd and 3rd is strictly for illustrative purposes and is not intended to depict any required order of assembly.

The basic structure is a thermosol lamina which is preferably directly adhered to a compressible lamina.

The thermosol material containing the phenolic material is adhesively very aggressive, particularly with regard to the epoxy impregnated compressible laminas. Epoxy impregnated laminas are usually very difficult to adhere well.

The compressible lamina is preferably that shown in U.S. Patent 3,147,698 which is a highly porous felted fibrous sheet impregnated with an elastomeric material. The preferred elastomeric impregnant is one that includes an epoxy resin. Other compressible materials having voids therein can also be used, for example, impregnated paper materials, foamed lamina and even cork laminas. The voids preferably comprise at least 20% of the volume of the lamina. While not preferred, the compressible lamina itself can be a composite material formed of two or more laminas or plies.

As shown in Figure 1, the basic structure can have a woven textile secured to the compressible lamina of the basic structure. The woven textiles used to date are rubber impregnated and in order to provide the desired adhesion to the textile a rubber adhesive layer, generally about 2 mils (0.05 mm) thick is used to secure the textile to the compressible lamina. However, a preferred securing adhesive layer would be a thermosol. The textile gives additional lateral strength to the laminate. A pressure sensitive adhesive is then applied to the exposed face of the woven textile and this is covered with a release sheet. The thus constructed resilient compressible printing element is normally utilized by removing the release sheet and sticking the element to the impression cylinder with the thermosol lamina facing the type face.A draw sheet or tampon sheet would usually be engaged over the thus exposed 1 st compressible lamina (looking at Figure 1). However the preferred thermosol lamina can itself function as an excellent working surface and is a considerable improvement in press packing elements, in this sense, eliminating the need for draw sheets and the like. The compressible lamina provides for the good compressibility of the printing element and the thermosol lamina enhances this even more than the prior art facings.

It is also frequently desired to build up multiple layers of compressible laminas alternating with laminas of thermosol. It has been found that the individual lamina of compressible material should preferably be from about 10 to about 50 (0.25 to 1.25 mm), and more preferably about 20 to about 30 (0.5 to 0.75 mm), mils thick to give optimum compressibility qualities. Preferably the individual thermosol lamina is at least about 2 mils (0.05 mm) thick and more preferably about 5 to about 75(0.125 to 1.88 mm), most preferably about 10 to about 20 (0.25 to 0.5 mm) thick, particularly when employed with multiple compressible plies. The thermosols thickness contributes to both overall laminate thickness and the quality of impact resistance.

To build up the multiple alternating layers it is preferable to join each compressible lamina to the adjacent compressible lamina by directly engaging each with the opposed faces of a single thermosol lamina without the use of intervening layers. Thus, 1st, 2nd and 3rd compressible laminas may be joined together by 1 sot and 2nd thermosol laminas as shown in Figure 1. If a thermosol working face is desired this composite structure or subassembly can be faced with a thermosol on one face. If desired for lateral strength the other face of the subassembly may be faced with a woven textile and pressure sensitive adhesive as shown in Figure 1.

Alternatively the thermosol working face may be replaced with a woven textile working face. The woven textile can be secured by rubber adhesive to the compressible lamina or preferably by a thermosol.

Other constructions of the resilient compressible printing element are, of course, possible. In some applications it is desirable to add additional alternate intermediate laminas of compressible material and thermosol or even other materials such as dimensionally stabilizing woven textiles.

Another aspect of the resilient compressible printing element which is unexpected is that it can have a lamina with a tensile stress (as determined by ASTM D142-61T) at least as high as about 800 psi (55 kg/cm2) or even the more preferred at least as high as about 1000 psi (70 kg'cm2) disposed between the printing member or other impinging force member and the compressible lamina and still have the compressible material operate effectively. This is admirably done by the thermosol lamina of the present invention but it is within the scope of the invention to cover any resilient compressible printing element having a new lamina with such unexpected characteristics.

Turning now to the process of the present invention, it will be understood that, in a preferred form, the thermosol coating is applied as a liquid by coating onto a lamina such as the compressible lamina previously described. A preferred form of the process is shown in Figure 2. As shown compressible lamina 10 may be withdrawn from a roll 11. The thermosol coating is applied by the simplest method giving a substantially uniform coating thickness, as illustrated by knife coater 12 and bank ofthermosol 13. The coated lamina 10 is passed through an oven 14 where it may be heated to say, about 200"F to 2200F (93 to 1 040C) to cause gelling and the formation of a solid thermoplastic material. The resulting laminate 15 its then rolled up in roll 16.The procedure of forming laminate 15 is considered to be a first stage 17 of the process. This laminate 15 would be the basic structure of Figure 1 before it is thermoset and could, of course, be thermoset in this configuration.

The process will now be described in a preferred embodiment, illustrated in Figure 2, when the two outer faces are of woven textile. Only the three compressible laminas secured together by two thermosol laminas subassembly formation is illustrated in Figure 2.

To form the subassembly laminate roll 16 is divided into two rolls 16a and 16b by cutting means 18. Rolls 16a and 16b are then positioned for unwinding and processing in a second or curing stage 19 ofthe process.

A roll 1 1a such as original roll 11 is positioned to be unwound providing a lamina 10a to be plied with the laminates 15a and 15b. Guide rolls 20 and 21 may be provided for directing the feeds into parallel relation.

Direction change rolls 22 and 23 may be provided for directing the composite about curing drum 24. The curing drum may be operated at a temperature of, say, 300"F to 3200F (149 to 1 600C) at its face. It has been found preferable to engage the lamina 10a directly against the curing drum 24 to reduce the risk of blisters forming at its interface with the thermosol layer to which it is to be joined. Both laminates 16a and 16b preferably have their thermosol laminas facing toward the curing drum so as to bring about a curing of the thermosol laminas from their unattached faces inwardly. Thus a good adherence of the thermoplastic thermosol composition is achieved with the adjacent compressible laminas being pressed against it before the thermosol becomes thermoset.The plied composite of lamina 11 a and laminates 1 6a and 1 6b is in contact with the surface of the drum for a time sufficient to bring about the adherence of the composite and curing of the thermosol, generally approximately 5 minutes in the Examples that follow. The composite is pressed together and againstthe drum 24 by an endless rotocure belt 26 which is held in position by rolls 27, 28 and 29. The newly formed composite or subassembly laminate 30 is then rolled up in a roll 31. It may be necessary to heat the laminate 30 further after its formation to assure complete curing, for example by passing the laminate 30 through the oven 14. Many other curing devices and procedures could obviously be employed. It is felt that it is important to cure the thermosol laminas from their open or exposed faces inwardly for best results.

To apply the outer woven textile laminas to the outer faces ocf the subassembly 30 just formed at stage 19 the roll 31 may be positioned as roll 11 in stage 17 and drawn past knife coater 12 where a rubber adhesive is applied as a solvent cement to its outer face to a thickness of, say, 2 mils (0.05 mm). The rubber coated composite is passed through the oven 14 to remove the solvent and then the textile is substantially immediately laid over the exposed face of the rubber and pressed thereon by passing between two rolls after which the composite is wound up. The composite is then turned over and a woven textile is applied to the other side of the subassembly 30 in a similar manner.Thereafter a pressure sensitive adhesive is applied over one of the textile faces by passing this latest composite back through stage 17 but a release sheet is applied over the exposed face of the pressure sensitive adhesive. It is preferably to use a thermosol to secure the woven textile to the subassembly 30.

subassembly 30 in a similar manner. Thereafter a pressure sensitive adhesive is applied over one of the textile faces by passing this latest composite back through stage 17 but a release sheet is applied over the exposed face of the pressure sensitive adhesive. It is preferable to use a thermosol to secure the woven textile to the subassembly 30.

If an outer face of the resilient compressible printing element is to be a thermosol working face then the roIl 1 1a of stage 19 of Figure 2 would be coated on its face toward the curing drum 24 with a cured thermosol lamina. This cured thermosol laminate can be formed as shown in stage 17 except the roll 16 is rerun through stage 17 without the operation of the coater 12 and with the oven operated at about, for example, 340-350 F (171 -177 C) to cure the thermosol.The laminate 15 with the thermosol cured is then placed in stage 19 in the position of lamina 10a and fed into the composite with the cured thermosol lamina disposed against the curing drum 24 and the exposed face of the compressible lamina against the thermosol lamina of laminate 1 5a. A woven textile can be applied to the side of the composite opposite the working face as previously described.

It is obvious that the process can be variously modifed, for example by cutting the press packing laminate to size rather than rolling it up in roll 25 or providing alternative coating as curing procedures.

The invention is further illustrated by the following Examples: Example 1 Athermosol composition was prepared by charging the following ingredients in the order in which they are listed to a reactor while stirring. The reactor was maintained at 75"F (24 C) during the charging sequence and the rate of charging was as rapid as reasonably possible allowing fortheir even dispersion within the reactor.

% of Total Parts Composition 1. Dioctyl phthalate 60 2. Polyvinyl chloride resin, dispersion grade (Geon 121, 78.7 B. F. Goodrich) 100 3. Phenolic resin (SP6600, Schenectady Chemical, Inc.) 25 12.3 4. Trimethylol propanetrime thacrylate monomer (X980, Rohm and Haas) 15 07.4 5. Stabilizer, barium-cadmium zinc (6V6A, Ferro Chemical Corp.) 3 01.5 6. 40% organic peroxide on inert filler (Luperco 231 XL, Penwalt Corp.) 0.3 00.1 203.3 100% After complete mixing which required approximately 45-60 minutes the thermosol composition was a thick liquid having the viscosity of about 20,000-30,000 cps and ready for use. It was retained in barrels for about 3 days at ambient conditions prior to use.A highly porous felted fibrous sheet impregnated with an elastomeric material Buna N latex and an epoxy resin that is a condensation product of epichlorohydrin and bisphenol Awhich is crosslinked with polyamide, was prepared in general accordance with U.S. Patent 3,652,376.

As is illustrated in Figure 2, a 25 mil (0.63mm) thick sheet of the highly porous compressible material was drawn from a roll and through coating station or stage 17. A conventional knife coater 12 applies the thermosol liquid which is maintained in a bank 13 at the knife blade in conventional manner. The thermosol was applied in a single pass to a thickness of 12 to 14 mils (0.3 to 0.35mm) and passed immediately through an oven for a dwell time of 5 minutes. The thermosol was gelled to a non-tacky solid in the oven. After the now 2-ply laminate exited the oven it was rolled up. The coated material was then cut into two rolls. This was actually done by unrolling part of a roll and cutting it off rather than bisecting a roll as depicted for illustration in Figure 2.

The thus formed and identical laminates were then positioned in relative position as depicted in Figure 2 and drawn from their respective rolls with their thermosol laminas facing toward the curing drum 24. A compressible lamina identical to the one described above was then fed between the two laminate sheets and the drum 24. The thermosol coated sides of the laminates thus engaged with unfaced exposed compressible lamina faces. The surface of a curing drum 24 was maintained at about 320"F (160 C) under a belt tension (belt 26) of about 10,000 Ibs (4536 kg) to provide a firm pulling together of the faces of the separate plies producing an adhered composite having a thickness of 100 mils (2.5 mm).

This composite was then run back through the oven of station 17 operated at about 345-F (174at) for a dwell time of about 5 minutes to assure cure of the thermosol. The cured composite was then returned to station 17 and coated with solution of nitrile rubber adhesive to a thickness of 2 mils (0.05 mm) and passed through the oven 14 operated at about220 F (104"C) with the same in oven time as before to remove the solvent. A 10 mil (0.25 mm) thick woven textile impregnated with nitrile rubber was applied over the nitrile rubber adhesive and firmed thereto by passing between closely spaced rollers. The thus formed composite was turned over and run back through station 17 and the procedure just described repeated except the woven textile was 5 mils (0.13 mm) thick. The composite was then passed back through station 17 and an acrylic pressure sensitive adhesive was applied to the exposed face of the 5 mils (0.13 mm) thick textile to a thickness of approximately 2 mils (0.05 mm) and passed through the oven at approximately 310-330"F (154-166"C) for a 5 minute dwell time and a release sheet applied thereover in the same manner as the previous application of the woven textiles.

The press packing laminate of Example 1 was tested on a standard letterpress machine and found to perform in a superior manner to present commercial press packing.

Example 2 The procedure of Example 1 was repeated except that a roll of the gelled thermosol laminate produced in the first station 17 of the process was cured by being passed back through the oven of station 17 without being additionally coated. The oven was operated at about 345"F (174 C) and the laminate had a dwell time of about 5 minutes in the oven. The thus formed cured laminate was then taken to the compilation-curing station 19 and positioned in place of roll 11 a with the cured thermosol lamina facing the curing drum 24. This composite was then run back through the oven of station 17 operated at 340 to 350"F (171 to 1770C) for a dwell time of 5 minutes to assure cure of the thermosol.The cured composite was then returned to station 17 and a woven textile lamina and pressure sensitive adhesive and release sheet were added as described in Example 1 to provide the laminate of Figure 1 having the thermosol working face.

The press packing laminate of Example 2 was tested on a standard letterpress machine and found to perform in a superior manner to present commercial press packing.

Example 3 The procedure of forming the cured laminate of the basic structure of Figure 1 was carried out as described in Example 2 and then the woven textile, pressure sensitive adhesive and release sheet were added to the exposed face of the compressible lamina as described in Example 2 to produce a press packing laminate having only the basic structure plus sub-laminas directly adjacent to the compressible lamina.

The press packing laminate of Example 3 was tested on a standard letterpress machine and found to perform in a superior manner to present commercial press packing.

A single thermosol lamina 60 mils (1.5 mm) thick was formed and tested on a Scott Tester and found to have a tensile of 1,600-1,900 p.s.i. (112-134 kg/cm2), an elongation of 200-250%, and a tensile stress at 100% elongation of 1,200-1,500 p.s.i. (84-105 kg/cm2) and tested on a durometer and found to have a Shore A hardness of 83-85.

From a processing standpoint, the procedure of the present invention elimates the use of solvents for the laminas that are thermosol and also the necessity of using adhesives of different characteristics on the facing surfaces, the compressible lamina and the resilient lamina (the thermosol) to provide an adhesion between them that will withstand the long term use to which printing elements are normally exposed. The phenolic component of the thermosol is important in lending stiffening properties of a desirable and generally indeterminant character. In addition the identically same lamina that provides the adhesion between laminas and internal stability can also provide a working face and vice versa. This working face even lends itself to grinding when desired to achieve a very exacting caliper.

Further, the flexibility of the manufacturing procedure provided is very great. Rolls of compressible material coated with gelled but unset thermosol can be prepared in advance and then variously combined to meet needs on a tailor-made basis. In addition multiple plies may be secured together and the whole composite cured in a single pass over a curing drum. Thus inventory requirements, labor productivity, plant space productivity and energy productivity are greatly increased.

It has been found in printing test runs that when the thermosol coating overlies the compressible lamina so that the thermosol lamina is engaged either with the drawsheet or with the back of the material that is being printed, the composite is extremely resistant to sinking over a long life, providing an unexpectedly superior printing press packing. Even more importantly, the print quality is superior-sharp and clear. While the compressible lamina provides good compressibility in the printing element, its compressible performance is enhanced by the thermosol work surface compared to prior art facings. Furthermore, the integrity of the laminate is excellent.

Present day press packing does not offer such superior printing performance and long life or such superior adaptability to the simplest type of assembly of a basic component into a multi-ply composite.

Claims (37)

1. A resilient compressible press-packing laminate comprising a compressible lamina and a lamina which is a solid non-compressible heat-set composition.

2. A laminate according to claim 1, wherein the heat-set composition is derived from a polyvinyl polymer plastisol and a crosslinkable polyacrylate.

3. A laminate according to claim 2, wherein said heat-set composition comprises 30 to 95% by weight polyvinyl plastisol and 2 to 20% by weight of polyacrylate.

4. A laminate according to claim 1,2 or 3, wherein the compressible lamina comprises voids.

5. A laminate according to claim 4, wherein the compressible lamina voids comprise at least 20% of the volume of said lamina and said heat-set lamina has a tensile stress of at least 800 psi.

6. A laminate according to any one of the preceding claims, wherein said compressible lamina comprises a fibrous sheet impregnated with an impregnant comprising an epxoxy resin and said heat-set composition comprises 2 to 30% by weight phenolic resin.

7. A laminate according to claim 6, wherein said heat-set composition has a polyvinyl plastisol content of 70 to 90%, polyacrylate monomer content of 3 to 10% and phenolic content of 8 to 15% by weight.

8. A laminate according to any one of the preceding claims, wherein said heat-set composition forms the outer working face for the laminate element.

9. A laminate according to any one of the preceding claims comprising a woven textile lamina over said compressible lamina.

10. A laminate according to claim 9 comprising a pressure sensitive adhesive over and in direct contact with said woven textile opposite the compressible lamina.

11. A laminate according to any one of the preceding claims comprising a second lamina on the opposite side of said heat-set composition from the first said compressible lamina.

12. A laminate according to claim 11, wherein said second lamina is a second compressible lamina and said compressible lamina is in direct face-to-face contact with the heat-set composition, and which comprises a second heat-set lamina in direct face-to-face contact with said compressible lamina, and a third compressible lamina in direct face-to-face contact with said second heat-set lamina.

13. A laminate according to claim 12 comprising a woven lamina in face-to-face engagement with the third compressible lamina opposite the second heat-set lamina.

14. A laminate according to claim 12 comprising a third heat-set lamina in face-to-face engagement with the third compressible lamina opposite the second heat-set lamina and forming an outer working face for the laminate.

15. A laminate according to claim 12, wherein the composition in each heat-set lamina comprises 70 to 90% by weight polyvinyl chloride plastisol, 3 to 10% by weight polyacrylate monomer, to 15% by weight phenolic resin and .01 to 1% by weight of a peroxide-free radical initiator; and each compressible lamina comprises a highly porous felted fibrous sheet impregnated with an impregnate comprising epoxy resin.

16. A laminate according to any one of the preceding claims, wherein the compressible lamina is at least 10 mils (0.25 mm) thick and the heat-set lamina is at least 2 mils (0.05 mm) thick.

17. A laminate according to claim 1 substantially as hereinbefore described.

18. A resilient compressible press-packing laminate comprising a first lamina that is compressible and a second lamina having a tensile stress of at least 800 psi. (55 kg/cm2).

19. A laminate according to claim 18, wherein said second lamina is intended to be positioned between the direction of the printing indicia and the compressible lamina, and has a tensile stress of at least 1,000 psi (70 kg/cm2) and is a thermosol.

20. A laminate according to claim 19, wherein said thermosol comprises a polyvinyl plastisol and a material crosslinkable therewith to form a thermoset polymer.

21. A laminate according to claim 18 substantially as hereinbefore described.

22. A process for manufacturing a resilient compressible press-packing laminate which comprises applying a liquid thermosol coating at least 2 mils (0.05 mm) thick onto a compressible lamina, solidifying said thermosol coating, thereafter, in a second step, curing said thermosol coating to its thermoset state.

23. A process according to claim 22, wherein said solidifying is by heating to cause gelling and said thermosetting is by heating to a higher temperature.

24. A process according to claim 23, wherein after solidification of said thermosol coating a second lamina is engaged directly against its exposed face and adhered to said face by being pressed against it during the thermosetting heating thereof.

25. A process according to claim 24, wherein said thermosetting heat is applied from the exposed face of the thermosol coating inwardly.

26. A process according to claim 23, wherein at least two laminates consisting of one lamina of gelled solidified thermosol and one compressible lamina are prepared and plied with at least one additional compressible lamina with the exposed face of each of the thermosol laminas being engaged directly against an exposed face of one of said compressible laminas, and said plied laminas being pressed together and heated from said exposed face of each thermosol coating inwardly to adhere said laminas into a composite and cure said thermosol.

27. A process according to claim 26, wherein each of said thermosol laminas is 5 to 75 mils (0.125 to 1.88 mm) thick and each of said compressible laminas is 10 to 50 mils (0.25 to 1.25 mm) thick.

28. A process according to claim 26, wherein each of said thermosol laminas is 10 to 20 mils (0.25 to 0.5 mm) thick and comprised of a thermosol composition comprising 70 to 90% by weight polyvinyl polymer containing plastisol, 2 to 10% by weight polyacrylate monomer and 8 to 15% by weight phenolic resin, and each of said compressible laminas is 20 to 30 mils (0.5 to 0.75 mm) thick.

29. A process according to any one of claims 22 to 28 for preparing a laminate as claimed in any one of claims 1 to 21.

30. A process according to claim 22 substantially as described in Example 1 or 2.

31. A laminate whenever manufactured by a process as claimed in any one of claims 22 to 30.

32. A thermosol composition comprising 30 to 95% by weight polyvinyl polymer containing plastisol, 2 to 20% by weight material crosslinkable with said polyvinyl polymer to form a thermoset polymer and 2 to 30% by weight phenolic resin.

33. A thermosol composition according to claim 32 comprising a peroxide free radical initiator and wherein said material is a polyacrylate monomer.

34. A thermosol composition according to claim 32 or 33, wherein said polyvinyl plastisol polymer is a polyvinyl chloride and said material is a di- or tri-acrylate monomer.

35. A thermosol composition according to claim 34 comprising .01 to 1 % by weight of a peroxyketal free radical initiator, wherein the plasticizer of said plastisol is dioctyl phthalate present in an amount of 15 to 65% by weight of the plastisol and the acrylate monomer is trimethylolpropane trimethacrylate present in an amount of 3 to 10% by weight of the total composition, the plastisol being present in an amount of 70 to 90% by weight and the phenolic resin being of the thermosetting two-step type present in an amount of 8 to 15% by weight.

36. A thermosol composition according to claim 35, wherein the polyvinyl polymer containing plastisol is present in an amount of 75 to 85% by weight and has a plasticizer content of 25 to 55% by weight, the polyacrylate monomer is present in an amount of 5 to 9% by weight and the phenolic resin is present in an amount of 11 to 13% by weight.

37. Athermosol composition according to claim 32 substantially as hereinbefore described.