SOFT HAND COPOLYAMIDE COMPOSITION

Abstract

Composition comprising, on a weight basis, the total being equal to 100%: from 98% to 100% of at least one copolyamide bearing amide units and polyether units, having a melting point (T.sub.m) from about 90 to about 150 C., in particular from about 100 C. to about 125 C., and having a flexural modulus of less than 100 MPa, as determined according to standard ISO 178 (2010); from 0 to 2% of at least one additive chosen from stabilizers and dyes, or a mixture thereof, for the manufacture of a heat-sensitive adhesive, in particular a veil, a film, granules, a filament, a grate, a powder or a suspension.

Claims

1. A method of using a heat-sensitive adhesive, comprising the steps of: a) forming a heat-sensitive adhesive composition of a HMA (hot-melt adhesive) type, consisting of a composition comprising on a weight basis, the total being equal to 100%: from 98% to 100% of at least one copolyamide bearing amide units and polyether units, having a melting point (T.sub.m) from about 100 C. to about 125 C., and having a flexural modulus of less than 100 MPa, as determined according to standard ISO 178 (2010); the said amide unit being 6/12, with a weight proportion of the long chain aliphatic repeat unit C12 of the amide unit being from 50% to 95%, the polyether units being derived from polytetramethylene glycol (PTMG), the weight proportion of polyether units in the copolyamide being greater than 40%, from 0 to 2% of at least one additive chosen from stabilizers and dyes, or a mixture thereof wherein the form of said heat-sensitive adhesive is selected from the group consisting of a veil, a film, granules, a filament, and a grate; b) melting said heat-sensitive composition by heating; c) applying said adhesive to at least one of a first part or a second part of a lamination, wherein said first part comprises a material comprising at least one of: cotton, spandex, polyamide, and polyester and said second part comprises a material comprising at least one of: cotton, spandex, polyamide, and polyester; d) allowing said heat-sensitive adhesive composition to cool thereby forming the lamination.

2. The method of claim 1, wherein the weight proportion of the long chain aliphatic repeat unit C12 of the amide unit is 70% to 80%.

3. The method of claim 1, wherein the adhesive is in the form of a veil.

4. The method of claim 1, wherein said adhesive has a thickness of from 5 to 30 micrometers for a veil, 20 to 100 micrometers for a film, and 10 to 50 micrometers for a grate, and said adhesive has an adherence of greater than 3 N/cm to said first part or said second part, as determined by the T peel test at 100 mm/min.

5. The method of claim 1, wherein said adhesive has an adherence of about 14 N/cm, as determined by the T peel test at 100 mm/min, to a first part comprising a material comprising a cotton/polyester mixture at a ratio of 90/10, for a thickness of about 30 m with a lamination temperature of 120 C.

6. The method of claim 1, wherein said adhesive has an adherence of about 12 N/cm, as determined by the T peel test at 100 mm/min, to a first part comprising a material comprising spandex, for a thickness of about 30 m with a lamination temperature of 120 C.

7. The method of claim 1, wherein said adhesive has an adherence from about 11 to about 22 N/cm, as determined by the T peel test at 100 mm/min, to a first part comprising a material comprising a cotton/polyester mixture at a ratio of 90/10, for a thickness of about 60 m with a lamination temperature of from 140 C. to 180 C.

8. The method of claim 1, wherein said adhesive has an adherence of greater than about 5 N/cm, as determined by the T peel test at 100 mm/min, to a first part comprising a material comprising at least one of cotton or spandex, for a thickness of about 55 to about 90 micrometers with a lamination temperature of from 140 to 160 C.

9. The method according to claim 1, having a loss of adherence after at least two washes at 40 C. from about 2% to about 18%.

10. The method of claim 1, wherein the weight proportion of polyether units in the copolyamide is between about 40% and about 80%.

11. The method of claim 1, wherein the weight proportion of polyether units in the copolyamide is about 50%.

12. The method of claim 1, wherein the method is used to manufacture sports articles.

13. A heat-sensitive adhesive comprising, on a weight basis, the total being equal to 100%: from 98% to 100% of at least one copolyamide bearing amide units and polyether units, having a melting point (T.sub.m) from about 90 to about 150 C., and having a flexural modulus of less than 100 MPa, as determined according to standard ISO 178 (2010); the said amide unit having the following structure:
(A).sub.x/(B).sub.y/(C) resulting from the condensation of unit (A), unit (B), and unit (C), in which: x=0 or 1, y=0 or 1 and x+y=1 or 2, A and B corresponding to an aliphatic repeating unit chosen from a unit obtained from at least one amino acid and a unit obtained from at least one lactam, or a unit X.Y obtained from the polycondensation of: at least one diamine chosen from a linear or branched aliphatic diamine, a cycloaliphatic diamine, and an aromatic diamine or a mixture thereof, and at least one dicarboxylic acid chosen from an aliphatic diacid, a cycloaliphatic diacid, and an aromatic diacid, the diamine and the diacid comprising from 4 to 36 carbon atoms; (C) represents a long-chain aliphatic repeating unit, obtained from an amino acid, a lactam, or a unit X.Y, of C10 or more, or a mixture thereof, and (A) and (B) being different from each other when they are both present, and (A) and (B) being different from (C) when they are present alone or together, the weight proportion of polyether units in the copolyamide being greater than 40%, from 0 to 2% of at least one additive chosen from stabilizers and dyes, or a mixture thereof, wherein the form of the heat-sensitive adhesive is selected from the group consisting of a veil, a film, granules, a filament, a grate, a powder, and a suspension.

14. The heat-sensitive adhesive of claim 13, wherein the form of the heat-sensitive adhesive is selected from the group consisting of a veil, a film, granules, a filament, and a grate.

15. The heat-sensitive adhesive of claim 13, wherein the form of the heat-sensitive adhesive is a veil.

Description

DESCRIPTION OF THE FIGURES

[0195] FIG. 1 shows the initial adhesion (or adherence) force in N/cm as a function of the lamination temperature, of films of 30 m or 60 m of TPU (1: Tm=100 C., 2: Tm=120 C., 3: Tm=150 C.) or of the invention (6/12/PTMG (1000/1000, MW amide units and polyether units, respectively): composition 1, Tm=110 C.) laminated on cotton (cotton: 90%, polyester: 10%) or Lycra at various temperatures.

[0196] From left to right:

[0197] Lamination temperature=120 C.: 14 N/cm: 6/12/PTMG and 4 N/cm: TPU1 (films of 30 m on cotton);

[0198] Lamination temperature=120 C.: 12 N/cm: 6/12/PTMG and 6 N/cm: TPU1 (films of 30 m on Lycra);

[0199] Lamination temperature=140 C.: 11 N/cm: 6/12/PTMG and 2 N/cm: TPU2 (films of 60 m on cotton);

[0200] Lamination temperature=160 C.: 16 N/cm: 6/12/PTMG, 4 N/cm: TPU2 and 2 N/cm: TPU3 (films of 60 m on cotton);

[0201] Lamination temperature=180 C.: 22 N/cm: 6/12/PTMG and 3 N/cm: TPU3 (films of 60 m on cotton).

[0202] Irrespective of the film thickness, the fabric used and the lamination temperature, the adhesion (or adherence) of the films of the invention is very markedly superior to that of the three TPUs used.

[0203] FIG. 2 shows the resistance to washing at 40 C. of films of 60 m of TPU (2: Tm=120 C., 3: Tm=150 C.) or of the invention (6/12/PTMG (1000/1000 MW amide units and polyether units, respectively): composition 1, Tm=110 C.) on cotton (cotton: 90%, polyester: 10%) as a function of the lamination temperature.

[0204] From left to right:

[0205] Lamination temperature=140 C.: 82%: 6/12/PTMG and 50%: TPU2;

[0206] Lamination temperature=160 C.: 98%: 6/12/PTMG, 79%: TPU2 and 50% TPU3;

[0207] Lamination temperature=180 C.: 98%: 6/12/PTMG and 67%: TPU3.

[0208] The resistance to washing at 40 C. of the films of the invention is very markedly superior to that of the TPUs irrespective of the lamination temperature.

[0209] FIG. 3 shows the resistance to washing at 60 C. of films of 60 m of TPU (1: Tm=100 C., 2: Tm=120 C., 3: Tm=150 C.) or of the invention (6/12/PTMG (1000/1000, MW amide units and polyether units, respectively): composition 1, Tm=110 C.) on cotton (cotton: 90%, polyester: 10%) or Lycra as a function of the lamination temperature.

[0210] Lamination temperature=120 C.: 91%: 6/12/PTMG and 17%: TPU1 (films of 30 m on cotton);

[0211] Lamination temperature=120 C.: 89%: 6/12/PTMG and 71: TPU1 (films of 30 m on Lycra);

[0212] Lamination temperature=140 C.: 73%: 6/12/PTMG and 25%: TPU2 (films of 60 m on cotton);

[0213] Lamination temperature=160 C.: 75%: 6/12/PTMG, 66%: TPU2 and 25% TPU3 (films of 60 m on cotton);

[0214] Lamination temperature=180 C.: 98%: 6/12/PTMG and 60%: TPU3 (films of 60 m on cotton).

[0215] The resistance to washing at 60 C. of the films of the invention is very markedly superior to that of the TPUs irrespective of the lamination temperature, the textile used or the thickness of the film.

EXAMPLES

Example 1: Compositions of the Invention

[0216] Compositions are prepared according to the techniques known to those skilled in the art. The melting point is measured by DSC (differential scanning calorimetry) according to standard 11357-3 (2013) or according to DIN 53736, Volume B (visual determination of the melting point of semi-crystalline polymers) optically using a heating bench and a microscope.

[0217] Composition 1: 6/12/PTMG (1000/1000, PA6/PA12 (30/70). DSC 1.sup.st heating: 114.8 C. [0218] The composition is detailed in Table I below:

TABLE-US-00007 TABLE I Starting material Weight Unit Sebacic acid 4.63 kg PTMG1000 22.46 kg Lactam 6 5.40 kg Lactam 12 12.60 kg Water 4.00 kg Anti-UV 225.00 g Antioxidant 135.00 g Zirconium butoxide 67.50 g

[0219] Composition 2: 6/12/PTMG (1000/1000, PA6/PA12 (25/75)).

[0220] DSC 1.sup.st heating: 124.6 C. [0221] The composition is detailed in Table II below:

TABLE-US-00008 TABLE II Starting material Weight Unit Sebacic acid 4.63 kg PTMG1000 22.46 kg Lactam 6 4.50 kg Lactam 12 13.50 kg Water 4.00 kg Anti-UV 225.00 g Antioxidant 135.00 g Zirconium butoxide 67.50 g

[0222] Composition 3: 6/11/12/PTMG (1000/1000, PA6/PA1/PA12 (20/10/70)). [0223] DSC 1.sup.st heating: 116.5 C. [0224] The composition is detailed in Table III below:

TABLE-US-00009 TABLE III Starting material Weight Unit Sebacic acid 4.63 kg PTMG1000 22.46 kg Lactam 6 3.60 kg Amino 11 1.80 Lactam 12 12.60 kg Water 4.00 kg Anti-UV 225.00 g Antioxidant 135.00 g Zirconium butoxide 67.50 g

Example 2: Test of Adhesion (or Adherence) of the Compositions of the Invention

[0225] Lamination machine: model HP-450M,MS [0226] Pressure: 1.0 kg/cm.sup.2 [0227] Bonding time: 25 sec [0228] Peeling machine: Hongda Tensometer [0229] Peel test at 100 mm/min [0230] Type of HMA [0231] 6/12/PTMG (composition 1) [0232] 3 different types of aliphatic or aromatic TPU: TPU1: Tm=100 C., TPU2: Tm=120 C., TPU3: Tm=150 C., sold by Bayer under the brand name Desmopan or BASF under the brand name Elastollan. [0233] Types of textiles: [0234] Cotton (cotton 90%, polyester 10%) [0235] Lycra The adhesion (or adherence) tests are presented in FIG. 1.

Example 3: Resistance to Washing

[0236] The various heat-sensitive adhesives are subjected to two machine washes for 1 hour 30 minutes for each wash and then to drying.

[0237] The washing tests are presented in FIGS. 2 and 3.

[0238] Comparison of the Heat-Sensitive Adhesive Properties

[0239] Table IV presents the comparison of the properties of a heat-sensitive adhesive consisting of a composition of the invention (6/12/PTMG: 1000/1000): composition 1 with those of TPU or of a standard copolyamide.

TABLE-US-00010 TABLE IV PROPERTIES TPU Standard CoPA Composition 1 Soft hand ++ + Resistance Up to 40 C. From 40 C. to 90 C. Up to 60 C. to washing Yellowing + + Implementation + +

[0240] - means that the product does not have the property under consideration.

[0241] + means that the product has the property under consideration in a satisfactory manner.

[0242] ++ means that the product has the property under consideration in an excellent manner.

[0243] The soft hand determines the flexibility of the compound.

[0244] The comparison of the observed properties shows that only the adhesive of the invention has the four properties described in this figure.

[0245] Table V shows the comparison of the major properties of various heat-sensitive adhesives.

TABLE-US-00011 TABLE V 6/6.12/11/ PEG.12 at 6/12/PTMG 25/20/25/30 (1000/1000) Standard Comparative Composition PROPERTIES TPU CoPA composition 1 Modulus at 5 300 200 90 23 C. Resistance Up to From 40 C. to Up to Up to to washing 40 C. 90 C. 40 C. 60 C. Tm 80 to 80 to 100 C. 110 C. 150 C. 135 C.

[0246] The TPUs have a suitable modulus but are not resistant to washing. Moreover, they are difficult to implement for the preparation of films.

[0247] The standard CoPAs show very good resistance to washing but have an excessively high modulus for the heat-sensitive adhesive application. 6/6.12/11/PEG. 12 shows poor resistance to washing and moreover has an excessively high modulus for the heat-sensitive adhesive application.

[0248] Only the compounds of the invention of CoPA/PTMG type have both satisfactory modulus and wash-resistance values.