Removable adhesive composition and a label containing it

Patent metadata

Field	Value
Publication number	US-12570879-B2
Application number	US-201917614685-A
Country	US
Kind code	B2
Filing date	May 31, 2019
Priority date	May 31, 2019
Publication date	Mar 10, 2026
Grant date	Mar 10, 2026

Abstract

The invention relates to a removable adhesive composition and uses of the adhesive composition in different kinds of labels and label laminate applications. In addition, the present invention relates to a label and a label laminate containing the removable adhesive composition.

First claim

The invention claimed is:

1 . A removable adhesive composition comprising an acrylic polymer, an amide wax having a particle size distribution of 0.5-20 μm and optionally a plasticizer and/or a tackifier, wherein the acrylic polymer comprises 70% to 99% by weight of at least one C5 to C10 alkyl (meth)acrylate, 0.5% to 5% by weight of at least one monomer having at least one acid or acid anhydride group, 0.5% to 5% by weight of at least one monomer having at least one amide group, 0% to 20% by weight of at least one C1 to C4 alkyl (meth)acrylate and 0% to 5% by weight of at least one hydroxyalkyl (meth)acrylate.

2 . The adhesive composition of claim 1 comprising:
the water based acrylic polymer in an amount of 78-98% based on the dry weight of the adhesive composition,
the amide wax in an amount of 2-22% based on the dry weight of the adhesive composition,
the plasticizer in an amount of 0-10% based on the dry weight of the adhesive composition, and
the tackifier in an amount of 0-15% based on the dry weight of the adhesive composition.

3 . The adhesive composition of claim 2 comprising:
the water based acrylic polymer in an amount of 90-98% based on the dry weight of the adhesive composition,
the amide wax in an amount of 2-10% based on the dry weight of the adhesive composition, and
the plasticizer in an amount of more than 0 to 3% based on the dry weight of the adhesive composition.

4 . The adhesive composition of claim 1 , wherein the amide wax is selected from amide waxes having a softening point in the range of 85-151° C.

5 . The adhesive composition of claim 1 , wherein the amide wax is selected from ethylene-bis-stearamide (EBS), a modified EBS or mixtures thereof.

6 . The adhesive composition of claim 1 , wherein the acrylic polymer comprises 2-ethylhexyl acrylate (EHA), acrylic acid (AA) and acryl amide (AM) and/or diacetone acrylamide (DAAM) and optionally butyl acrylate (BA), methyl methacrylate (MMA) and/or hydroxyethyl methacrylate (HEMA).

7 . The adhesive composition of claim 1 , wherein the amount of an insoluble fraction of the polymer in the composition is at least 60.

8 . The adhesive composition of claim 1 , wherein the adhesive composition exhibits G′ below 40 000 Pa at 100 rad/s at 25° C.

9 . The adhesive composition of claim 1 , wherein the adhesive composition exhibits G″ below 20 000 Pa at 100 rad/s at 25° C.

10 . The adhesive composition of claim 1 , wherein the adhesive composition has the loss factor, tan δ, above 0.3 at 100 rad/s at 25° C.

11 . The adhesive composition of claim 1 , wherein the adhesive composition has the glass transition temperature (Tg) below −30° C.

12 . The adhesive composition of claim 11 , wherein the adhesive composition has the glass transition temperature (Tg) between −50° C. and −30° C.

13 . The adhesive composition of claim 1 , wherein the adhesive composition exhibits 90° peel on PET below 7 N with a coated paper when measured according to FINAT standard (2014) FTM2 Peel adhesion (90°).

14 . The adhesive composition of claim 1 , wherein the adhesive composition exhibits tack below 7 N with a coated paper, when measured according to FINAT standard (2014) FTM9 Loop Tack.

15 . A label laminate comprising a face layer, an adhesive layer and a release liner, wherein the adhesive layer comprises the adhesive composition of claim 1 .

16 . A label comprising a face layer and an adhesive layer comprising an adhesive composition comprising an acrylic emulsion, an amide wax having a particle size distribution of 0.5-20 μm and optionally a plasticizer and/or a tackifier, wherein the acrylic polymer of the adhesive composition comprises 70% to 99% by weight of a C5 to C10 alkyl (meth)acrylate, 0.5% to 5% by weight of a monomer having at least one acid or acid anhydride group, 0.5% to 5% by weight of a monomer having at least one amide group, 0% to 20% by weight of a C1 to C4 alkyl (meth)acrylate and 0% to 5% by weight of a hydroxyalkyl (meth)acrylate.

17 . The label according to claim 16 , wherein the adhesive composition comprises:
the water based acrylic polymer in an amount of 78-98% based on the dry weight of the adhesive composition, the amide wax in an amount of 2-22% based on the dry weight of the adhesive composition, the plasticizer in an amount of 0-10% based on the dry weight of the adhesive composition, and the tackifier in an amount of 0-15% based on the dry weight of the adhesive composition.

18 . The label according to claim 17 , wherein the adhesive composition comprises:
the water based acrylic polymer in an amount of 90-98%, based on the dry weight of the adhesive composition, the amide wax in an amount of 2-10%, based on the dry weight of the adhesive composition, and the plasticizer in an amount of more than 0-3%, based on the dry weight of the adhesive composition.

19 . The label of claim 16 , wherein the amide wax of the adhesive composition is selected from amide waxes having a softening point in the range of 85-151° C.

20 . The label of claim 19 , wherein the adhesive composition has the glass transition temperature (Tg) below −30° C., between −50° C. and −30° C.

21 . The label of claim 16 , wherein the amide wax of the adhesive composition is selected from ethylene-bis-stearamide (EBS), a modified EBS or mixtures thereof.

22 . The label of claim 16 , wherein the acrylic polymer of the adhesive composition comprises 2-ethylhexyl acrylate (EHA), acrylic acid (AA) and acryl amide (AM) and/or diacetone acrylamide (DAAM) and optionally butyl acrylate (BA), methyl methacrylate (MMA) and/or hydroxyethyl methacrylate (HEMA).

23 . The label of claim 16 , wherein the amount of an insoluble fraction in the adhesive composition is at least 60%.

24 . The label of claim 16 , wherein the adhesive composition exhibits G′ below 40 000 Pa at 100 rad/s at 25° C.

25 . The label of claim 16 , wherein the adhesive composition exhibits G″ below 20 000 Pa at 100 rad/s at 25° C.

26 . The label of claim 16 , wherein the adhesive composition has the loss factor, tan δ, above 0.4 at 100 rad/s at 25° C.

27 . The label of claim 16 , wherein the adhesive composition has the glass transition temperature (Tg) below −30° C.

28 . The label of claim 16 , wherein the adhesive composition exhibits 90° peel on PET below 7 N with a coated paper when measured according to FINAT standard (2014) FTM2 Peel adhesion (90°).

29 . The label of claim 16 , wherein the adhesive composition exhibits tack below 7 N with a coated paper, when measured according to FINAT standard (2014) FTM9 Loop Tack.

30 . A labelled item comprising a label according to claim 16 attached onto the surface of the item.

Assignees

• Upm Raflatac Oy

Inventors

• Zhong Yu
• Janicki Bartosz
• Karhu Johanna

Classifications

• C09J7/385

  Acrylic polymers · CPC title

• C09J2301/408

  additives as essential feature of the adhesive layer · CPC title

• G09F3/10

  by an adhesive layer · CPC title

• C09J2203/334

  as a label · CPC title

• C08F220/1808

  C8-(meth)acrylate, e.g. isooctyl (meth)acrylate or 2-ethylhexyl (meth)acrylate · CPC title