A release liner comprising nanofibrillar cellulose

Patent metadata

Field	Value
Publication number	US-2017190799-A1
Application number	US-201415314222-A
Country	US
Kind code	A1
Filing date	Jun 26, 2014
Priority date	Jun 26, 2014
Publication date	Jul 6, 2017
Grant date	—

Abstract

The invention relates to a method for obtaining a release liner and to release liner comprising a primer layer and a cellulose based support layer, the primer layer comprising an organic compound having one or more functional vinylic groups, the organic compound comprising an acetal connecting a first moiety and a second moiety, the first moiety comprising nanofibrillar cellulose having functional hydroxyl groups and the second moiety comprising an organic fragment, the organic fragment comprising at least one functional vinylic group.

First claim

1 . A method for obtaining a substrate layer for a release liner comprising nanofibrillar cellulose, the method comprising:
providing a cellulose based support layer, providing an organic compound comprising a first moiety and a second moiety connected by an acetal by arranging an acetalisation reaction between nanofibrillar cellulose and an organic fragment, and applying the organic compound on a surface of the cellulose based support layer to form a release liner comprising a primer layer and the cellulose based support layer,
wherein after the acetalisation reaction the first moiety comprises the nanofibrillar cellulose obtained from a primary cellulose having functional hydroxyl groups and the second moiety comprises the organic fragment, the organic fragment comprising at least one functional vinylic group.

2 . The method according to claim 1 , wherein the first moiety and the second moiety are connected by a hemiacetal.

3 . The method according to claim 1 , further comprising:
disintegrating the primary cellulose to the nanofibrillar cellulose by mechanical means.

4 . The method according to claim 1 , further comprising:
oxidizing the primary cellulose or the nanofibrillar cellulose to provide nanofibrillar cellulose having functional aldehyde groups to at least some extent.

5 . The method according to claim 1 , wherein the nanofibrillar cellulose comprises an amount of functional aldehyde groups of at least 0.02 mmol/g, preferably at least 0.05 mmol/g of the amount of the primary cellulose.

6 . (canceled)

7 . The method according to claim 1 , wherein the organic fragment participating in the acetalisation reaction is
an unsaturated aldehyde having a general formula
CH 2 ═CH—(CH 2 ) n —CH═O, wherein n =1 to 17,

preferably an undecylenic aldehyde having a formula
CH 2 ═CH—(CH 2 ) 8 —CH═O,

a 4-pentenal having a formula
CH 2 ═CH—(CH 2 ) 2 —CH═O, or

a 2,2-dimethyl-4-pentenal having a formula
CH 2 ═CH—CH 2 C(CH 3 ) 2 —CH═O, or

an unsaturated alcohol having a general formula
CH 2 ═CH—(CH 2 ) n —CH—OH, wherein n =1 to 17,

such as an undecylenic alcohol having a formula
CH 2 ═CH—(CH 2 ) 8 —CH—OH, or

preferably a diol comprising at least one functional vinylic group.

8 . (canceled)

9 . The method according to claim 1 , wherein the organic fragment participating in the acetalisation reaction is a water soluble carrier polymer having functional hydroxyl groups, the water soluble carrier polymer comprising at least one functional vinylic group.

10 . (canceled)

11 . The method according to claim 1 , wherein the cellulose based support layer is paper, preferably coated paper having a grammage equal to or more than 38 g/m2, for example in the range of 38 to 150 g/m2.

12 .- 13 . (canceled)

14 . The method according to claim 1 , wherein the primer layer comprises the nanofibrillar cellulose equal to or less than 5%, such as in the range of 0.1 to 5%, preferably equal to or less than 4%, such as in the range of 0.2 to 3.5%, most preferably equal to or less than 3%, such as in the range of 0.3 to 3% by weight of the primer layer.

15 . The method according to claim 1 , wherein the nanofibrillar cellulose has a number-averaged diameter equal to or less than 400 nm, preferably 200 nm, preferably 100 nm.

16 .- 19 . (canceled)

20 . A substrate layer for a release liner comprising a primer layer and a cellulose based support layer, the primer layer comprising an organic compound having one or more functional vinylic groups, the organic compound comprising an acetal connecting a first moiety and a second moiety, the first moiety comprising nanofibrillar cellulose having functional hydroxyl groups and the second moiety comprising an organic fragment, the organic fragment comprising at least one functional vinylic group.

21 . The substrate layer for a release liner according to claim 20 , wherein the first moiety and the second moiety are connected by a hemiacetal.

22 . The substrate layer for a release liner according to claim 20 , wherein the nanofibrillar cellulose comprises functional aldehyde groups, for example at least 0.02 mmol/g, preferably at least 0.05 mmol/g.

23 . The substrate layer for a release liner according to claim 20 , wherein the organic fragment comprises a linear or branched, saturated or unsaturated hydrocarbon chain having 2 to 20 carbon atoms, optionally interrupted by heteroatoms of N, O, or S, the organic molecule comprising at least one functional vinylic group.

24 . The substrate layer for a release liner according to claim 20 , wherein the organic fragment is obtainable from the acetalisation reaction of
an unsaturated aldehyde having a general formula
CH 2 ═CH—(CH 2 ) n —CH═O, wherein n= 1 to 17,

preferably an undecylenic aldehyde having a formula
CH 2 ═CH—(CH 2 ) 8 —CH═O,

a 4-pentenal having a formula
CH 2 ═CH—(CH 2 ) 2 —CH═O, or

a 2,2-dimethyl-4-pentenal having a formula
CH 2 ═CH—CH 2 C(CH 3 ) 2 —CH═O, or

an unsaturated alcohol having a general formula
CH 2 ═CH—(CH 2 ) n —CH—OH, wherein n= 1 to 17,

such as an undecylenic alcohol having a formula
CH 2 ═CH—(CH 2 ) 8 —CH—OH, or

preferably a diol comprising at least one functional vinylic group.

25 . (canceled)

26 . The substrate layer for a release liner according to claim 20 , wherein the organic fragment is obtainable from an acetalisation reaction of a water soluble carrier polymer having functional hydroxyl groups, the water soluble carrier polymer comprising at least one functional vinylic group.

27 . (canceled)

28 . The substrate layer for a release liner according to claim 20 , wherein the cellulose based support layer is paper, preferably coated paper having a grammage equal to or more than 38 g/m 2 , for example in the range of 38 to 150 g/m 2 .

29 .- 30 . (canceled)

31 . The substrate layer for a release liner according to claim 20 , wherein the nanofibrillar cellulose has a number-averaged diameter equal to or less than 400 nm, preferably 200 nm, preferably 100 nm.

32 . The substrate layer for a release liner according to claim 20 , comprising the nanofibrillar cellulose equal to or less than 5%, such as in the range of 0.1 to 5%, preferably equal to or less than 4%, such as in the range of 0.2 to 3.5%, most preferably equal to or less than 3%, such as in the range of 0.3 to 3% by weight of the primer layer.

33 . The substrate layer for a release liner according to claim 20 , further comprising a top layer, such as a release coating.

34 . A labelstock comprising the substrate layer for a release liner according to claim 20 and an adhesive label, the adhesive label attached to the primer layer side of the substrate layer for a release liner.

Assignees

• Upm Kymmene Corp

Inventors

• Rissanen Mikko
• Nuopponen Markus

Classifications

• C09J7/0235

  Chemistry & Metallurgy · mapped topic

• C09J7/0228

  Chemistry & Metallurgy · mapped topic

• C08B3/20

  Esterification with maintenance of the fibrous structure of the cellulose (surface esterification of textiles D06M13/00) · CPC title

• C09J2203/334

  as a label · CPC title

• C08B15/02 Primary

  Oxycellulose; Hydrocellulose; {Cellulosehydrate, e.g. microcrystalline cellulose} · CPC title