Title of Invention

CROSSLINKABLE BASE LAYER FOR BONDABLE INTERLININGS IN ACCORDANCE WITH THE DOUBLE DOT TECHNIQUE

Abstract

The present invention relates to a process for the coating and/or lamination of sheetlike structures in accordance with the double dot technique, wherein upper dot is based on an amine-terminated crosslinkable copolyamide and the lower dot is composed of an OH-terminated polyester and further comprises a cross linker, wherein the crosslinking component comes from the group of the isocyanates and has more than two reactive groups per molecule, and an acrylic and/or polyurethane dispersion.

Full Text

FORM 2 THE PATENTS ACT, 1970 (39 of 1970) COMPLETE SPECIFICATION (See Section 10) TITLE "CROSSLINKABLE BASE LAYER FOR BOND ABLE INTERLINING S IN ACCORDANCE WITH THE DOUBLE DOT TECHNIQUE" APPLICANT Degussa AG Bennigsenplatz 1 D-40474 Dusseldorf Germany Nationality : a German company The following specification particularly describes the nature of this invention and the manner in which it is to be performed Crosslinkable base layer for bondable interlinings in accordance with the double dot technique The invention relates to a crosslinkable adhesive coating based on a powder mixture comprising commercially customary, OH-group-terminated copolyethane based on terephthalic acid, isophthalic acia and butanediol or butanediol in combination with small amounts of up to 12 mol%, preferably from 6 to 10 ml, of other diols such as hexanediol or polyethylene glycerol or PTHF, having melting points of from 100 to 150°C, and a pulverized free or blocked isocyanate, an aqarium epichlorohydrin or a liquid or solid epoxide, producing a base dot as a barrier to strikebackin double dot coating. The upper dot consists of an and regulated copolyamide, in order to ensure attachment to the lower dot. The invention relatein in particular to a hotmelt adhesive composition for the halftone coating of bondable interlinings for the clothing industry, especially outerwear. In order to solve the problems regarding the refuced stability to laundering and dry cleaning and regarding the relatively weak adhesion, improved hotmelt adhensive compositions, but also improved coating technology, have been developed. Duodot or double dot coatings are DE-B 22 31 723, DE-B 25 36 911 and DE-B 32 30 579. The coating supports have been improved by using yarns with low-denier individual fibers down to the microf iber range and also synthetic yarns, examples being high-bulk acrylic yarns or polyester yarns.The wovens originally used have largely been replaced by stitch-bonded fabrics, which are a combination nonwovens and knitted fabrics. These new combination lead to very soft but also very open constructions which place even greater requirements on the coating material and hotmelt adhesive compositions, especially with regard to strikeback and strikethrough of the adhesive composition. Costs and quality reasons have led to a marked reduced or in the amount of coating applied per m2 of interlink material. Whereas formerly the amounts applied commonly 10 - 20 g/m2, they are nowadays 7-12g/m2, Despite these small amounts, it is necessary to ensure sufficient adhesion and resistance; in other words,the hotmelt adhesive must not strike away into the inter-lining, since then it would no longer be available for the actual bonding. The object on which the invention was based, therefore was to find an effective strikeback barrier which with reduced amount of coating features high bond strength, effective attachment of the upper dot to the base layer and high stability to laundering and dry cleaning. A range of strikeback barriers are known: crosslink the acrylate dispersions or polyurethane dispersions, powder-filled pastes based on high-melting and regulated copolyamides and polyethylene or on high-viscosity thermoplastic polyurethane powders. All systems have more or less severe disadvantages in terms of application, attachment to the upper dot stability to laundering. In addition, the dispersion cannot be employed on coarse, hairy interlinings. When self-crosslinking acrylate or polyurethane dispersions are coated, there is partial crosslinking even an the course of coating, which leads to a deposit on the stencils and thus to clogging of the stencil Laborious cleaning of the unit is required. Great diffi culties are experienced when there is production-inducing standstill. A further problem is the attachment of reducing upper dot to the base layer. The high-viscosity filled systems based on acid-regulated polyethylene and polyurethane do not achieve the required strikeback security.In DE 198 08 809 a description is given of how a from isocyanate is stabilized to water: the free isocyanate is incorporated by extrusion into an inert polyethylene mix and subsequently finely ground again. By this means success was achieved in creating a stable crosslinkable system for the base dot. The disadvantages of this system is the complicated and hence expersively preparation of the water-stable isocyatated additionally, the polyethylene matrix hinders the diffusion rate, which signifies a reduction in reaction rate. In a preferred embodiment a commercially cust omary copolyester with OH end groups is mixed wit. passivated trimerized diisocyanate (as described in DE 35 17 333 Al) and the mixture is processed as an aqueous paste by rotary screen printing. It has now surprisingly become possible to preparation very reactive system in accordance with the class, having an activation temperature in the range from about 100 to 130°C and having water resistance. The crosslinkable hotmelt adhesive composition according to the invention for the coating and/or lamination to sheetlike structures has the feature that the reading components present in the hotmelt adhesive composition do not react, with crosslinking, until in the melt. Polyisocyanates, particularly solid polyisocyanates, are dispersed with isocyanate-reactive media, such diamines (hexamethylenediamine) , and by that means are surface-stabilized with respect to the surroufrf the medium. This deactivation is brought about by treating the isocyanate particles on the surface with deactivating agent in amounts which are stoichiometric with respect to the total isocyanate content. The passivated fraction is in the range from 0.01 to preferably from 0.1 to 5%. It is also possible, however, to use other crosslinkers, such as aqueous epichlorohydrin or epoxides. In course of subsequent drying in the oven at about 100 130°C, crosslinking is initiated within a few seconds give a crosslinked strikeback barrier for the double dot. In this way it is possible to avoid the customary problems of isocyanate-containing systems, which are or example that capped isocyanates (with caprolactam or oximes as capping agent or obtained by dimerizati require excessive activation temperatures; further no extraneous substances should be released in the course of bonding. The other problem was that blocked isocyanates react with water while still in the paste. Suitable isocyanates are solid isocyanates contain the more than 2 free NCO groups and having a melting range of from 100 to 130°C (e.g. Vestanat T 1890 from Deguard AG) . The fraction of the polyisocyanate relative to the polyester used is in the range from 3 to 20% by weight, preferably from 5 to 10% by weight. Also suitable as crosslinking component are epoxides having a melting range of from 90 to 130°C, preferably from 100 to 120°C, a molecular weight range of from 2 000 to 6 000, preferably 2 500 to 3 000, and more than 2 epoxide groups per molecule; bisphenol A maybe mentioned as an example. A surprising finding was particularly effective attachment of the lower dot to the upper dot material employed. The amine-regulated copolyamide, as upper and material with the reactive components at the lower dot paste and formed an optimum attachment at the boundary of the two dots, which is not possible normal, acid-regulated polyamides. Suitable product with the base dot and upper dot are low-melting grades of low viscosity. The melting point should be between 90 and 150-C, preferably between 115 and 130°C, with a solving viscosity in the range from 1.2 to 1.7 preferably from 1-25 to 1.5. By this means, the boundary layer reacts with the crosslinker-containing past and creates a highly stable bonding of the two dots. The coating amounts for the base dot should be from 1 . 5 g/m2, preferably from 2 to 4 g/m2, and for the upper dot, depending on application, should be from 8 g/m , especially from 5 to 7 g/m . The base dot can be applied as a paste in a halftone formation. copolyamides employed are based on dicarboxylic and is with chain lengths of C6 - C15, C1, LL and diametry (piperazine, hexamethylenediamine, MPD, IPD C9 + C16 ). The fraction of the polyester (based on solids constant in the base paste is in the range from 1 to 20 by weight, preferably from 5 to 15% by weight. As acrylate and/or polyurethane dispersions is the possible to employ all common types. Particularly suitable are self-crossiinking butyl acrylates such PLEXTOL BV 411 from Degussa AG, for example. Polyester:acrylate (PU) ratio based on solids is 1:5 1:20, preferably 1:7 - 1:15. Examples: A powder mixture comprising an OH-terminated copolyester (VESTAMELT 4680-P1) and a trimerized polyisocyanate from Degussa (VESTAGON T 1890) was dispersed with a diametry (e. g. hexamethylenediamine) and a common dispersant.In water and the dispersion was passivated (diamine : equimolar deficit relative to NCO groups, 1:50. A CL ! * o common acrylate dispersion, e.g. PLEXTOL BV 441,and a thickener, e.g. Mirox TX, from Stockhausen, processed to a printable paste, as described in DE-B 20 07 971, DE-B 22 29 308, DE-B 24 07 505 DE-B 25 07 504, and the paste was printed with a rotary screen printing unit having a CP 66 stencil onto a polyester knit comprising high-bulk yarn. The amount applied was 3 g/m2. VESTAMELT X 1027-P816 scattered onto the paste dot while the dot was wet, the excess was removed by suction, and the material was dried and partially sintered in a drying oven at 130°C. The upper dot (VESTAMELT X 1027-P816) had an and on of 5 g/m , so that the overall weight was 8 g/m2 . Paste formulation of the base dot: 500 g of water 10 g of Mirox TX (polyacrylic acid derivative) 20 g of Intrasol 12/18/5 (ethoxylated fatty alcohol) 400 g of PLEXTOL BV 441 20 g of VESTAMELT 4680-P1 3 g of VESTANAT T 18 90 0.15 g of hexamethylenediamine Result: A 5 cm wide strip of this interlining was bonded to a siliconized shirt material comprising a polyester/contain blend at a joining temperature of 127 °C and a linear pressure of 4 N for 10 s, and then the assembly was subjected to laundering at 60°C. Primary adhesion: 13 N/ 5 cm 60~C wash: 10 N/ 5 cm Back-riveting: 0.1 N/10 cm Comparative example 1: (state of the art) A paste system based on an acid-regulated polyamide on a polyethylene was applied to the same interlin: and the material was scattered with the same upper material (VESTAMELT X 1027-P816), dried and sinter The same amounts of base dot and upper dot were applied Paste formulation: 1500 g of water 35 g of Mirox TX 40 g of Intrasol 12/18/5 400 g of Schattifix 1820 (LP polyethylene) 200 g of VESTAMELT 250-P1 Schattifix 1820 is a low-pressure polyethylene having melting point of 128 - 130°C and an MFR of 20 g/10 min Result: Primary adhesion: 9 N/ 5 cm 60°C wash: 5 N/ 5 cm Back-riveting: 0.9 N/10 cm Comparative example 2: A paste system based on an acid-regulated polyamide and on an acrylate dispersion was applied to the interlining and the material was scattered with the upper dot material (VESTAMELT X 1027-P816), dried sintered. The same amounts of base dot and upper were applied. Paste formulation: 500 g of water 10 g of Mirox TX 20 g of Intrasol 12/18/5 400 g of PLEXTOL BF 440 Primary adhesion: 6 N/ 5 cm 60°C wash: 3 N/ 5 cm Back-riveting: 1.9 N/10 cm The advantage of the new technology is that the lower dot is crosslinked even under the drying conditions and owing to its amine termination, the upper dot is linked with the lower dot during melting, so giving an optimum attachment. Since there is a sharp increase in the molecular weight of the lower dot following coating, it is no longer able to sink into the knit. In the course of subsequent bonding, the low-viscosity polyamide of the upper dot is compelled to flow against the upper material that is to be bonded, since it is unable to flow off downward, hence giving very high adhesions even with very small amounts of hotmed adhesive. The parting layer between upper dot and dot, which hitherto has been the weak point of the system, especially in the course of laundering, is resistant to hydrolytic attack than prior systems and therefore exhibits substantially higher stabilities. Products employed: VESTAMELT 4680-P1 is a copolyester from Degussa based on terephthalic acid, isophthalic acid, butaned and polyglycol, having a melting point of 120°C. VESTAMELT X 1027-P816 is a ternary copolyamide from Degussa AG with amine end groups 100 - 4 00 meq/eg, preferably 250 - 350 meq/kg, melting point 120°C. VESTANAT T 1890/100 is a polyisocyanate having a func tionality of 3 - 4, its melting point being at 100-115°C. It is a product of Degussa AG. PLEXTOL BV 411 PLEXTOL BV 411 is an aqueous dispersion of a self crosslinking acrylic polymer. O.Z. 6267-WO What is claimed is: 1. A hotmelt adhesive composition for the coating and/or lamination of sheetlike structures in accordance with the double dot technique, wherein upper dot is based on an amine-terminated crosslinkable copolyamide and the lower dot is composed of an OH-terminated polyester and further comprises a crosslinker and an acrylic and/or PU dispersion. 2. A hotmelt adhesive composition as claimed in claim 1, wherein the upper dot is an amine-regulated copolyamide. 3- A hotmelt adhesive composition as claimed in either of the preceding claims, wherein the upper dot is an amine-regulated copolyamide powder having a melting range of from 90 to 150°C and a solution viscosity eta rel in the range from 1.2 to 1.7. 4. A hotmelt adhesive composition as claimed in any of the preceding claims, wherein the lower dot is an OH- terminated copolyester. 5. A hotmelt adhesive composition as claimed in claim 1, wherein the lower dot comprises an acrylate dispersion and/or polyurethane dispersion. 6. A hotmelt adhesive composition as claimed in any of the preceding claims, wherein the crosslinking component comes from the group of the isocyanates and has more than two reactive groups per molecule. 7. A hotmelt adhesive composition as claimed in any of the preceding claims, wherein the isocyanate has a melting range of from 100 to 130°C. 8. A hotmelt adhesive composition as claimed in any of the preceding claims, wherein an epoxide having a melting range of from 90 to 130°C, a molecular weight range of from 2 000 to 6 000 and more than two epoxide groups per molecule is employed as crosslinking component. 9. A hotmelt adhesive composition as claimed in any of the preceding claims, wherein a pulverulent free or blocked isocyanate is employed as crosslinking component. 10. A hotmelt adhesive composition as claimed in any of the preceding claims, wherein the crosslinking component is an epichlorohydrin. 11. A hotmelt adhesive composition as claimed in any of the preceding claims, wherein the reactive, 0H- terminated copolyester is employed as base dot for the double dot technology, as a strikethrough barrier. 12. A hotmelt adhesive composition as claimed in any of the preceding claims, wherein the base dot consists of a passivated isocyanate and an OH-terminated copolyester and is applied in halftone formation as a paste. 13. A hotmelt adhesive composition as claimed in any of the preceding claims, wherein the crosslinking reaction is accelerated by catalysts. 14. A hotmelt adhesive composition as claimed in any of the preceding claims, wherein the copolyester is based on terephthalic acid and/or isophthalic acid and/or adipic acid and/or dodecanedioic acid and on butanediol and/or hexanediol and/or polyglycol and/or PTHF. 15. The use of a hotmelt adhesive composition as claimed in any of the preceding claims for the coating and/or lamination of sheetlike structures. 16. An interlining material for clothing, which has been provided with a hotmelt adhesive composition as claimed in any of the preceding claims.

Documents:

1204-chenp-2006 abstract-duplicate.pdf

1204-chenp-2006 claims-duplicate.pdf

1204-CHENP-2006 CORRESPONDENCE OTHERS.pdf

1204-CHENP-2006 CORRESPONDENCE PO.pdf

1204-chenp-2006 description (complete)-duplicate.pdf

1204-CHENP-2006 FORM 18.pdf

1204-CHENP-2006 FORM 3.pdf

1204-CHENP-2006 PETITIONS.pdf

1204-chenp-2006-abstract.pdf

1204-chenp-2006-claims.pdf

1204-chenp-2006-correspondnece-others.pdf

1204-chenp-2006-description(complete).pdf

1204-chenp-2006-form 1.pdf

1204-chenp-2006-form 26.pdf

1204-chenp-2006-form 3.pdf

1204-chenp-2006-form 5.pdf

1204-chenp-2006-pct.pdf