EP2245102A1 - Biodegradable hot-melt adhesive composition - Google Patents

Biodegradable hot-melt adhesive composition

Info

Publication number
EP2245102A1
EP2245102A1 EP09721207A EP09721207A EP2245102A1 EP 2245102 A1 EP2245102 A1 EP 2245102A1 EP 09721207 A EP09721207 A EP 09721207A EP 09721207 A EP09721207 A EP 09721207A EP 2245102 A1 EP2245102 A1 EP 2245102A1
Authority
EP
European Patent Office
Prior art keywords
preferably
composition according
acid
selected
melt adhesive
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP09721207A
Other languages
German (de)
French (fr)
Inventor
Christophe Robert
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bostik SA
Original Assignee
Bostik SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to FR0800809A priority Critical patent/FR2927629B1/en
Application filed by Bostik SA filed Critical Bostik SA
Priority to PCT/FR2009/000162 priority patent/WO2009115672A1/en
Publication of EP2245102A1 publication Critical patent/EP2245102A1/en
Application status is Withdrawn legal-status Critical

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09JAdhesives; non-mechanical aspects of adhesive processes in general; adhesive processes not provided for elsewhere; use of material as adhesives
    • C09J123/00Adhesives based on homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Adhesives based on derivatives of such polymers
    • C09J123/02Adhesives based on homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Adhesives based on derivatives of such polymers not modified by chemical after-treatment
    • C09J123/04Homopolymers or copolymers of ethene
    • C09J123/08Copolymers of ethene
    • C09J123/0846Copolymers of ethene with unsaturated hydrocarbons containing other atoms than carbon or hydrogen atoms
    • C09J123/0869Acids or derivatives thereof
    • C09J123/0884Epoxide containing esters
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09JAdhesives; non-mechanical aspects of adhesive processes in general; adhesive processes not provided for elsewhere; use of material as adhesives
    • C09J167/00Adhesives based on polyesters obtained by reactions forming a carboxylic ester link in the main chain; Adhesives based on derivatives of such polymers
    • C09J167/02Polyesters derived from dicarboxylic acids and dihydroxy compounds
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09JAdhesives; non-mechanical aspects of adhesive processes in general; adhesive processes not provided for elsewhere; use of material as adhesives
    • C09J167/00Adhesives based on polyesters obtained by reactions forming a carboxylic ester link in the main chain; Adhesives based on derivatives of such polymers
    • C09J167/04Polyesters derived from hydroxycarboxylic acids, e.g. lactones
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L23/00Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
    • C08L23/02Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
    • C08L23/04Homopolymers or copolymers of ethene
    • C08L23/08Copolymers of ethene
    • C08L23/0846Copolymers of ethene with unsaturated hydrocarbons containing other atoms than carbon or hydrogen atoms
    • C08L23/0869Acids or derivatives thereof
    • C08L23/0884Epoxide containing esters
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2666/00Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
    • C08L2666/02Organic macromolecular compounds, natural resins, waxes or and bituminous materials
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L91/00Compositions of oils, fats or waxes; Compositions of derivatives thereof
    • C08L91/06Waxes
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L93/00Compositions of natural resins; Compositions of derivatives thereof
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00Stock material or miscellaneous articles
    • Y10T428/13Hollow or container type article [e.g., tube, vase, etc.]
    • Y10T428/1352Polymer or resin containing [i.e., natural or synthetic]

Abstract

The invention relates to biodegradable hot-melt adhesive compositions, preferably without residual tackiness at room temperature and having a biodegradability, as measured by the released carbon-dioxide analysis method pursuant to Standard EN ISO 14855, that is higher than 55%, preferably higher than 60%, and preferably higher than 90%, and to the use thereof. This percentage is given by reference with the cellulose biodegradability measurement, which amounts to 100% in the same conditions.

Description

MELT ADHESIVE COMPOSITION BIODEGRADABLE

Field of the Invention.

The present invention relates to biodegradable hotmelt adhesive compositions and their use in many application areas, particularly in the field of packaging. Background of the invention. In the context of market developments towards so-called "organic" products, the major players in the retail look to their suppliers to request products to meet those expectations.

These expectations are even stronger than the European directives require the gradual establishment of so-called "compostable" satisfactory including the criteria in the European Standard ENI 3432. In this context, the ENI 3432 standard specifies that the biodegradability of product measured according to method EN ISO 14855 by analysis of evolved carbon dioxide must be greater than 90%.

In the areas of packaging in general, such as the closure of boxes and cases, assembling cardboard trays, or in the specific field of food packaging are commonly used adhesive compositions to bond papers printed on all type containing food or not, such as paper, bottles or jar, these containers sometimes being polystyrene, polypropylene, polylactic acid. Customer expectations in terms of compostable products are passed on suppliers of each part of the package and customers demand that each component of a product is biodegradable.

Thereby providing objects generally compostable or biodegradable packaging implies also the supply of hot melt adhesive compositions (or hot melt) compostable and / or biodegradable.

In this context, it is therefore for a hot melt adhesive to be also consistent with the biodegradability EN ISO 14855 while keeping all other properties of a standard hot melt glue, including the necessary properties for labeling purposes any type of food or not containing.

US 5312850 describes the production of hot melt adhesive compositions (hot melt) using certain ingredients known as biodegradable. These compositions comprise 20 to 98% by weight of polylactide polymer (PLA) containing at least 20 mol% of lactide monomer, 2 to 80% of a tackifying resin having a softening point according to ASTM E 26 60 0 C, 0 to 50% of a plasticizer and 0 to 30% of a wax as a diluting agent and 0 to 3% of a stabilizer agent. No indication is given as to the biodegradability of the final composition according to EN ISO 14855.

WO 95/10577 describes the production of hot melt adhesive compositions preferably pressure sensitive (hot melt pressure sensitive adhesive or HMPSA) said fully biodegradable / compostable by combining polyesters derived from lactic acid which are already known biodegradable polymers with plasticizing biodegradable resins based on polylactic acid (PLA), of molecular weight less than 20,000 and having a Tg of less than 60 0 C. No indication is given as to the biodegradability of the final composition in accordance with EN ISO 14855.

These compositions containing PLA are not adapted to the fields of food packaging because they have the disadvantages of being rather rigid and have too high a heat reactivation temperature for applications in the desired areas.

In the field of hot melt adhesive compositions without biodegradable PLA EP553394 describes the preparation of hot melt adhesive compositions comprising a specific polyester obtained from 3-hydroxy-butyric acid and 3-hydroxy-valeric. No indication is given as to the biodegradability of the final composition according to EN ISO 14855.

EP 741 178 also describes the production of biodegradable adhesive hot melt compositions comprising a specific polyester obtained by reaction between a dicarboxylic acid and an ether or diglycidyl ester. No indication is given as to the biodegradability of the final composition according to EN ISO 14855.

There is therefore a need for hot melt adhesive compositions compostable likely to meet the European standard EN ISO 14855 and which also satisfy all the properties of a standard hot melt adhesive properties for a particular application of labeling any food containing or no. Summary of the Invention.

The object of the present invention is to provide hot melt adhesive compositions, preferably without residual tack at ambient temperature (ie without tack or without power immediate tacky at room temperature), and biodegradability as measured by the analysis method carbon dioxide released in accordance with EN ISO 14855, is greater than 55%, preferably greater than 60%, preferably greater than 90%. This percentage is given by reference to the extent of biodegradability of the cellulose which is under the same conditions 100%.

To this end the invention provides:

A biodegradable hot melt adhesive composition comprising (A) from 30% to 90%, preferably 40% to 60%; or 45% to 55% by weight relative to the total weight of the adhesive composition of a (co) polymer selected from (Al) polycaprolactones, (A2) polyesters resulting from the condensation between a dicarboxylic acid of formula R - [COOH] 2 wherein R represents a hydrocarbon group having 2 to linear C30 or slightly branched or cyclic, saturated or unsaturated, mono or polyhydroxylated and a diol of formula R2 [OH] 2 wherein R2 represents a hydrocarbon group having 2 to C32 linear, slightly branched, cyclic or polycyclic, saturated, unsaturated or polyunsaturated mono or polyhydroxylated or (A3) copolymers of polycaprolactones (Al) and polyesters (A2); (B) from 10% to 50%, preferably from 20% to 40%, or 25% to 35% by weight relative to the total weight of the adhesive composition of a tackifier (or tackifier) having an average molecular weight M w between 300 and 5000 and chosen from:

- (i) natural or modified rosins of origin; - (ii) terpene resins resulting from the polymerization of terpene hydrocarbons in the presence of Friedel-Crafts catalysts, optionally modified by action of phenols;

- (iii) copolymers based on natural terpenes;

(C) from 10% to 30%, preferably 10% to 25% by weight relative to the total weight of the adhesive composition with a stiffening agent represented by a wax having a melting point in the range of 40 ° C to 150 ° C, preferably selected from optionally hydroxylated amide waxes, hydrogenated castor oil, oxidized synthetic waxes and non-functionalized or not, the polyethylene oxides, the weight average molecular weight is greater than 1000;

(D) 0% to 20%, preferably 3% to 7% by weight relative to the total weight of the adhesive composition of one or more additives selected from stabilizers, anti-oxidants, the blocking enhancement agents, the pigments, dyes or fillers. Preferably, in the composition according to the invention the (co) polymer (A) has an average molecular weight (Mn) ranging from 500 to lOOOOOg / mole, preferably from 2000 to 60000g / mol. Preferably, in the composition according to the invention, the dicarboxylic acid of formula R [COOH] 2 is selected from sebacic acid, succinic acid, adipic acid, aldaric, alpha-ketoglutarique, aspartic acid, azelaic acid, camphoric acid, fumaric acid, glutaconic acid, glutaric , itaconic, maleic, malic, malonic, meglutol, mesaconic, mesoxalic, 3-methylglutaconic.

Preferably, in the composition according to the invention, the diol of formula

R2 [OH] 2 is selected from linear diols structure, slightly branched, saturated or unsaturated, of the formula R2 [OH] 2 wherein R 2 represents a hydrocarbon group having C2 to C22, the diols of the formula HO - (- CH2- CH2-O-) n -H such that n is an integer from 1 to 6.

Preferably, in the composition according to the invention (B) is selected from rosin esters with glycerol or pentaerythritol, terpenes, phenol or terpenes, particularly terpene phenol softening point of between 100 ° C and 150 0 C. preferably, in the composition according to the invention (C) is selected from amide waxes oleamide type stearamide, ethylene bis-oleamide, ethylene bis stearamide, preferably those having a melting point between 60 ° C and 120 ° C.

Preferably, in the composition according to the invention (A) is a polyester obtained by reaction between monoethylene glycol and sebacic acid

(B) is a terpene phenolic resin;

(C) is an amide wax selected from oleamide or cis 1, 3 docosenamide erucamide; (D) represents an additive improving the blocking selected from polyethylene glycol, precipitated silica or a mixture thereof.

Furthermore, hot melt adhesives according to the invention also exhibit the following properties:

Depending on the type of formulations selected, they exhibit a viscosity in a range from 500 to 200,000 mPa · s, which makes them suitable for application on a flexible support or non-flexible support;

Depending on the type of formulations selected, they have a reactivation temperature of from about 40 0 C to 150 0 C which makes them suitable for any type of flexible or non-flexible application; for more specific applications on a flexible support, one will choose formulations whose reactivation temperature is in the range 60-1 10 0 C.

According to the chosen types of formulations, they have an open time adaptable to different types of applications; thus for delayed bonding applications on flexible support is chosen a hot melt adhesive having an open time almost zero or less than 1 second or preferably less than 0.5 sec; for applications on rigid support will be chosen a hot melt adhesive having an open time greater than or equal to 2 seconds, preferably 3 to 30 seconds or from 5 to 15 seconds.

According to one embodiment, the composition according to the invention has an open time measured on apparatus OLINGER less than 1 second, preferably less than 0.5 second).

According to one embodiment, the composition according to the invention has an open time measured on apparatus OLINGER greater than or equal to 2 seconds, preferably from 5 to 30 seconds).

According to another object the invention relates to the use of a composition according to the invention can be reactivated to create a seal between two non-flexible substrates, for example two boxes. Preferably the use is made with a composition with a viscosity between 500 and 20000 mPa.s for applications by melting pan and roller coating.

Preferably the use is made with a composition with a viscosity between 2000 and 50000 mPa.s for applications by melting pan or melter and spray coating.

Preferably the use is made with a composition whose viscosity is between 70,000 and 200,000 mPa.s for applications extruder and spray coating.

Preferably the invention relates to the use of a composition according to the invention for preparing biodegradable packaging non-flexible rigid for food or non-food use.

Preferably the invention relates to the use of a composition according to the invention for textile applications such as automotive or aeronautical packings, cosmetics, tobacco, pharmaceuticals, medical. Preferably the invention relates to the use of a composition according to the invention for the preparation rigid packaging, closing box and covers, cardboard tray formation, bottle labeling, bookbinding , the paperboard coating.

detailed discussion of embodiments of the invention. Description of the compositions according to the invention.

(A) Part polymer.

This part comprises a (co) polymer preferably having a molecular weight of 500 to 100000 g / mol, selected from (Al) polycaprolactones, (A2) polyesters resulting from the condensation between a carboxylic diacid of formula R [COOH] 2 wherein R represents a hydrocarbon group having 2 to linear C30 or slightly branched or cyclic, saturated or unsaturated, mono or polyhydroxylated and a diol of formula R2 [OH] 2 wherein R2 represents a hydrocarbon group having 2 to linear C32 weakly branched, cyclic or polycyclic, saturated, unsaturated or polyunsaturated mono- or polyhydroxylated or (A3) copolymers obtained from polycaprolactones (Al) and polyesters (A2) or a mixture thereof.

(A) represents from 30% to 90% preferably 40% to 60%; more preferably 45% to 55% by weight relative to the total weight of the adhesive composition.

(Al) The polycaprolactones are formed by reaction ring opening of epsilon-caprolactone monomer with an initiator mono-, di- or multi-functional wherein the functional groups, generally hydroxy groups, are suitable for performing a ring-opening reaction with momonères epsilon-caprolactone. In such reactions, the initiator will be a minor component and the weight ratio between initiator and monomer determines the molecular weight of the resulting polymer.

polycaprolactone polymers preferably have a molecular weight of 5000 to l00000 g / mol. (A2) The polyesters of the invention are formed by reaction between a dicarboxylic acid of formula R [COOH] 2 wherein R represents a hydrocarbon group having C2 to C30 linear or slightly branched or cyclic, saturated or unsaturated, mono or polyhydroxylated and a diol of formula R2 [OH] 2 wherein R 2 represents a hydrocarbon group having C2 to C32 linear, slightly branched, cyclic or polycyclic, saturated, unsaturated or polyunsaturated mono- or polyhydroxylated

Preferably, the diacid is selected alone or in mixture from:

1) a linear diacid, saturated or unsaturated natural or synthetic origin of formula R [COOH] 2 wherein R represents a hydrocarbon group having C2 to C30 such as succinic acid, glutaric acid, pimelic acid, acid azelaic acid, sebacic acid, traumatic acid, suberin (α, ω-diacids Cl 6 to C26);

2) a fatty acid obtained by dimerization of fatty animal or vegetable origin acid;

3) a mono- or poly-hydroxylated diacid such as tartaric acid, tartronic acid, aldaric acids;

4) an amino acid eg aspartic acid,

5) a diacid mono or polyhydroxylated saturated or unsaturated and / or slightly branched or unbranched, for example méglutol, 3-methylglutaconic acid, mesaconic acid, crocetin, the alkylitaconiques acids (chaetomelliques acids and cériporiques).

The dicarboxylic acids are preferably selected from, adipic, aldaric, alpha-ketoglutaric acid, aspartic acid, azelaic acid, camphoric acid, fumaric acid, glutaconic acid, glutaric acid, itaconic, maleic, malic, malonic, méglutol, mesaconic, mesoxalic, 3-methylglutaconic only or a mixture thereof.

Preferably, the diols are selected individually or in combination among:

1) a diol of linear, slightly branched, saturated or unsaturated structure of the formula R2 [OH] 2 wherein R2 represents a hydrocarbon group C2-C32.

2) a dimer diol derived from unsaturated fatty alcohols,

3) a diol of formula R2 [OH] 2 wherein R2 represents a hydrocarbon group mono- or poly-hydroxy saturated or unsaturated C2-Cl 2 4) a cyclic or polycyclic diol such as 1,2-cyclohexanedimethanol, diols derived from sugars such as l, 4: 3,6-dianhydro-D-glucitol (DAG), the l, 4: 3,6-dianhydro-D-mannitol (DAM), a l, 4: 3, 6-dianhydro-L-iditol (DAI).

5) R2 formula diols [OH] 2 wherein R 2 is monoethylene glycol or Polyethylene Glycol of the formula HO - (- CH2-CH2-O-) n -H such that n is between 1 and 6.

The diols are preferably selected from the linear structure diols, saturated or unsaturated, of structural formula R2 [OH] 2 wherein R 2 represents a hydrocarbon group having C2 to C22, the diols of the formula HO - (- CH2-CH2- O-) n -H wherein n is an integer from 1 to 6.

The polyesters of the invention preferably have an average molecular weight (Mn) between 500 and 100000 g / mol. The polyesters of the invention preferably having an MFI at 160 ° C under 2.16 kg comprised between 0.2 and 1000. Preferably, the polyester will have an average molecular weight (Mn) of from 2000 to 60,000 g / mol and an MFI of between 1 and 500 g / mol.

Preferably, the polyesters of the invention are obtained by reaction of the monoethylene glycol with sebacic acid. Preferably, when the selected diacid is an aromatic diacid, aromatic diacid content (from terephthalic or isophthalic acid type) in the polyester is less than 53 mol%, preferably less than 25%, especially less than 25% by isophthalic aromatic. (A3) copolymers obtained from polycaprolactones (Al) and polyesters (A2).

(B) Part tackifier (or tackifier).

The tackifying resins have average molecular weights M w generally between 300 and 5000 and are selected in particular from:

- (i) naturally occurring or modified rosins, such as for example the rosin extracted from pine gum, wood rosin extracted from the roots of the tree and their hydrogenated derivatives, partially hydrogenated, dimerized, polymerized or esterified with mono- or polyhydric alcohols such as glycerol; - (ii) terpene resins generally resulting from the polymerization of terpene hydrocarbons such as for example mono-terpene (or pinene) in the presence of Friedel-Crafts catalysts, optionally modified by action of phenols;

- (iii) copolymers based on natural terpenes, eg styrene / terpene, alpha-methyl styrene / terpene and vinyl toluene / terpene.

(B) represents from 10% to 50% preferably 20% to 40%, more preferably 25% to 35% by weight relative to the total weight of the adhesive composition.

(B) is preferably chosen from rosin esters with glycerol or pentaerythritol, terpenes, phenol or terpenes, particularly terpene phenol softening point between 100 0 C and 150 0 C.

These resins are commercially available, and from those having a softening temperature between 80 and 150 0 C, there may be mentioned for example in the above categories the following products:

(i) Sylvalite® ® RE 100S from Arizona Chemical, Dertoline® ® G2L and Dertopoline ® CG of the French company DRT;

(ii) DERTOPHENE T, H DERTOPHENE ® 150 from DRT; Sylvarez® ® TP95, Sylvarez® ® TPL 15 Arizona Chemical; Sylvares ® 2040 Arizona Chemical;

(iii) Sylvarez® ® ZT 105 LT from Arizona Chemical.

The temperature (or point) of softening of these resins is determined according to standardized test ASTM E 28, whose principle is the following. A brass ring diameter of about 2 cm is filled with the resin to be tested in the molten state. After cooling to room temperature, the ring and the solid resin are placed horizontally in a thermostated glycerin bath whose temperature can vary from 5 ° C per minute. A diameter steel ball about 9.5 mm is centered on the disk of solid resin. The softening temperature is - during the bath temperature up phase at 5 ° C per minute-the temperature at which the resin disk flue to a height of 25.4 mm under the weight of the ball. (C) Part stiffening agent.

These agents are waxes characterized by a melting point measured by differential scanning calorimetry DSC, between 40 0 C and 150 ° C preferably between 50 ° C and 100 ° C in the case of a coating on a flexible support deferred collage and between 100 ° C and 140 ° C in the case of an immediate gluing for application to flexible or non-flexible support.

These waxes are chosen from optionally hydroxylated amide waxes, hydrogenated castor oil, oxidized synthetic waxes and non-functionalized or not, the polyethylene oxides, the weight average molecular weight is greater than 1000.

Is used preferably waxes selected from ethylene bis stearamide, ethylene bis oleamide, stearamide, paraffins, Fischer-Tropsch waxes, oleamides, the "cis-3-docosenamide, erucamide, the ethylene glycol monostearate, palmitate céthyle, saturated linear alcohols, carboxylic acids. preferably used yet, waxes chosen from waxes amide oleamide type stearamide, ethylene bis-oleamide, ethylene bis-stearamide, more preferably the amide waxes such oleamide, stearamide, ethylene melting point of bis-oleamide between 60 ° C and 120 ° C.

(C) represents from 10% to 30% preferably 10% to 25% by weight relative to the total weight of the adhesive composition.

(C) is preferably an amide wax selected from oleamide or cis 1, 3 docosenamide erucamide.

(D) Part additives.

In the composition according to the invention to improve certain properties optionally can be used an amount of 0% to 20%, preferably 3% to 7% by weight relative to the total weight of the adhesive composition of one or more additives.

These additives are selected from stabilizers, antioxidants, agents for improving the blocking, pigments, dyes or fillers. (D) Stabilizers (or antioxidant) are introduced to protect the composition from degradation resulting from a reaction with oxygen which is likely to occur by the action of heat, light or catalysts residual on certain raw materials such as tackifying resins.

Using the compounds selected from tetrakis 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, acrylate, 2- (l- (2-hydroxy-3,5 ditertiopenthylphényl) ethyl ) -4,6-ditertiopentylphényl the pentaérythrityltetrakis (3-laurylthiopropionate), the aromatic polycarbodiimide, substituted diarylcarbodiimide, the aromatic polycarbodiimide. Any primary antioxidants are used which trap free radicals and are generally substituted phenols like Irganox ® 1010 from CIBA (Tetrakis 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate pentaerythritol). The primary antioxidants may be used alone or in combination with other antioxidants such as phosphites like Irgafos ® 168 also from CIBA, or with UV stabilizers such as amines.

(D2) The enhancement agents are introduced including the blocking to prevent adhesion of the coated side of hot melt adhesive on the printed side during the production and storage of coils. Eg for applications wrapping yogurt.

These compounds are selected from ethylene bis-stearamide, ethylene bis oleamide, stearamide, oleamide, cis-3-docosenamide, erucamide, ethylene glycol monostearate, cetyl palmitate, saturated linear alcohol carboxylic acid.

Can also be used preferably polyethylene glycol or precipitated silica.

(D3) Pigments and dyes are introduced to modify the color of the adhesive without changing the other properties.

(D4) the fillers are introduced to enhance the cohesion of the adhesive, reducing the cost, or change the adhesive performance by adjusting the amount and nature of the introduced load. These compounds are selected from talc, carbonates, silica, kaolin, sulfates, clays. Process for preparing the compositions.

The hot melt composition according to the invention is prepared by simple mixing of its components at a temperature between 100 and 200 ° C, until a homogeneous mixture. Required * mixing techniques are well known in the art. Properties of the compositions according to invention P.

The compositions exhibit all the necessary properties to be biodegradable melt adhesive compositions. Biodegradability.

They exhibit biodegradability measured according to the analysis method of carbon dioxide released (EN ISO 14855) of greater than 55%, preferably greater than 60%, more preferably greater than 90%. This percentage is given by reference to the biodegradability of the cellulose which is under the same conditions 100%. These biodegradability results show that hot melt adhesives including biodegradability, according to EN ISO 14855, is greater than 90% are excellent candidates to meet the criteria of the European standard ENI 3432 on goods known as "compostable". The compositions of the invention reach this level of biodegradability after 6 months and preferably as soon as 45 days.

The adhesive compositions are preferably non-pressure sensitive, without residual tack at ambient temperature. Insofar as the compositions of the invention show no residual tack at ambient temperature, does not introduce any plasticizer because they are usually liquid at room temperature and their melting point is low, below 25 ° C.

Successful formulations also have the following properties: Viscosity.

The final viscosity of the hotmelt adhesive according to the invention is dependent on the nature of the components used, their respective quantity and their molar mass.

Depending on the type of formulations selected, hot melt adhesives have a viscosity in a range from 500 to 200,000 mPa · s at the temperature of application, which makes them suitable for applications according to different types of processes or tools for implementing, on a flexible support or non-flexible support.

Thus when the viscosity is between 500 and 20,000 mPa.s at the application temperature can be targeted applications by melting pan and roller coating.

When the viscosity is between 2,000 and 50,000 mPa.s at the application temperature can be targeted applications by melting pan or melter and spray coating. When the viscosity is between 70,000 and 200,000 mPa.s at the application temperature applications can be targeted by extruder and spray coating. reactivation temperature.

Depending on the type of formulations selected, hot melt adhesives have a reactivation temperature ranging from about 40 ° C to 150 ° C which make them suitable for any type of flexible or inflexible application. Thus, for more specific applications on a flexible support, one will choose formulations whose reactivation temperature is in the range 60-1 10 ° C.

The choice of the polymer has an impact on the temperature of reactivation of the final composition. In contrast to formulations comprising the polymer (A) according to the invention, some prior art polymers do not allow to obtain hot melt adhesives with target reactivation temperatures. In fact it was noted reactivation temperatures above 150 0 C in the J and K formulations of Comparative Examples when the component A is PLA (poly lactic acid) or an aromatic copolyester.

According to a particular mode, a reactivation temperature between 60 0 C and 90 ° C will in particular enable the hot melt adhesive to be sealed on yoghurt pots during the formation thereof.

Yoghurt pot banner is printed paper hotmelt coated onto widths (roll width) of about 1300 mm with the coating process described above.

This streamer is then cut, positioned around the yoghurt pots and reactivated, that is to say heated to a temperature above the reactivation temperature to reflow slightly melt adhesive ( "hot melt") and cause adhesion between the banner paper and the thermoplastic polymer into the pot as polystyrene, polypropylene or polylactic acid. Open time. Depending on the type of formulations selected, hot melt adhesives have an open time adaptable to different types of applications on flexible or non-flexible support. The open time depends mainly recrystallization temperatures of the various components, their glass transition temperature and also quantities thereof. Thus advantageously, the compositions according to the invention have an open time less than 1 second or preferably less than 0.5 second, for example for delayed bonding applications on a flexible support.

This feature allows the hot melt adhesive to instantly freeze once placed on the paper rolls. So rewinding the coated coil glue itself can be performed immediately after gluing.

For applications on rigid support such as cardboard, one would select a hot melt adhesive having an open time greater than or equal to 2 seconds, preferably 3 to 30 seconds.

Moreover, the formulations also have the following required properties of hot melt adhesives. Thermal stability.

Sufficient thermal stability for the changing properties of the adhesive due to its deterioration is not noticeable during a typical use of the product on a suitable equipment. residual tackiness (éfialement referred to immediate sticky).

These formulas show no residual tackiness (non sticky at room T °). Blocking: These formulas resist pressurization and temperature of the hot melt adhesive layer between two substrates without the hot melt adhesive or printing medium is transferred from one side to the other. Sliding. These formulas also have a sliding behavior allowing these coatings on paper formulations may be used on production lines without damaging or fouling the drive systems and without slipping on storage reels. Compatibility. The choice of the individual components of the formula has also an impact on their overall compatibility in the final composition. Indeed, all mixtures fail to systematically obtain homogeneous compositions. Indeed one could note a lack of compatibility in formulations I and L comparative examples when the C component is a paraffin. Use of the compositions according to the invention.

The compositions according to the invention are suitable for any type of packaging for food or non-food applications.

Among the types of packaging include flexible packaging or non-flexible. Among the non-rigid flexible packages include the cash closures and covers, stage training carton, bottle labeling, binding, paper coating the cardboard that can be reactivated to create a seal.

Examples: The following examples are intended to illustrate the invention without l