Patent application EP20178977A (EP), filed 2020-06-09
Publication number: EP3753972A1
Title: CASEIN CROSS-LINKING PROCESS AND CASEIN-DERIVED CROSS-LINKED POLYMERIC MATERIAL
Abstract: [0001]    A casein cross-linking process for obtaining a casein-derived cross-linked polymeric material comprises the steps of: mixing casein (11) with water (12) and with at least one cross-linking agent (13), to obtain a paste (10); shaping the paste (10) to give it a shape, in particular a shape of a slab, to obtain a shaped object (20); heating the shaped object (20) to a cross-linking temperature and keeping heated for a heating time interval, wherein during the heating time interval the shaped object is subjected to pressing and, at the cross-linking temperature and during the heating time interval, the at least one cross-linking agent promotes formation of bonds between casein macromolecules, to obtain an object (50) of polymeric material which is formed by a cross-linked structure of casein macromolecules; leaving the object (50) of polymeric material to dry. The casein-derived cross-linked polymeric material, which in particular is obtained from that process, can be used to make products of said polymeric material, such as buttons (70) for items of clothing.
IPC codes: A44B   1/    02            A I
C08H   1/    00            A I
C08J   3/    24            A I
C08L  89/    00            A I
Claims: number: 1
text: Casein cross-linking process for obtaining a casein-derived cross-linked polymeric material, comprising the steps of:
number: 2
text: Casein cross-linking process according to claim 1, wherein the quantity of water (12) mixed in with the casein (11) has a weight of between 5% and 40% of casein's weight, in particular between 15% and 25% of the casein's weight, and
wherein the quantity of the at least one cross-linking agent (13) mixed in with the casein (11) has a weight of between 0.1% and 15% of the casein's weight, in particular between 4% and 10% of the casein's weight.
number: 3
text: Casein cross-linking process according to claim 1 or 2, wherein the casein (11) is rennet casein, in particular powdered rennet casein.
number: 4
text: Casein cross-linking process according to any of claim 1 to 3, wherein said at least one cross-linking agent (13) is a free-radical generating compound.
number: 5
text: Casein cross-linking process according to claim 4, wherein the free-radical generating compound is a peroxide or a persulphate, in particular the free-radical generating compound is sodium persulphate or potassium persulphate.
number: 6
text: Casein cross-linking process according to claim 4 or 5, wherein a first cross-linking agent is a free-radical generating compound and a second cross-linking agent is an epoxide compound having two or more epoxide groups.
number: 7
text: Casein cross-linking process according to claim 6, wherein the epoxide compound having two or more epoxide groups is neopentyl glycol diglycidyl ether or bisphenol A diglycidyl ether.
number: 8
text: Casein cross-linking process according to claim 6 or 7, wherein, in the step of mixing casein (11) with water (12) and at least one cross-linking agent (13), the quantity of epoxide compound and the quantity of free-radical generating compound have a weight-based ratio between each other which is less than 5, in particular is between 0.5 and 4.
number: 9
text: Casein cross-linking process according to any of claims 1 to 8, wherein the cross-linking temperature is between 50°C and 120°C, in particular between 70°C and 90°C, and wherein the heating time interval is between 2 and 16 hours, in particular between 6 and 9 hours.
number: 10
text: Casein cross-linking process according to any of claims 1 to 9, wherein the step of heating the shaped object (20) is preceded by a step of pressing at room temperature in which the shaped object (20) is subjected to pressing for a pressing time interval, the pressing time interval being in particular between 1 hour and 12 hours, even more in particular between 1 hour and 3 hours,
and/or
wherein the step of heating the shaped object (20) is followed by a step of pressing at room temperature in which the object (50) of cross-linked polymeric material is subjected to pressing for a pressing time interval, the pressing time interval being in particular between 8 hours and 60 hours, even more in particular between 20 hours and 48 hours.
number: 11
text: Casein cross-linking process according to any of claims 1 to 10, wherein, during pressing, the object (20; 50) is subjected to a pressure of more than 20 bar, in particular to a pressure of more than 150 bar, even more in particular to a pressure of between 250 bar and 450 bar.
number: 12
text: Cross-linked polymeric material obtained through the process according to any of claims 1 to 11.
number: 13
text: Cross-linked polymeric material derived from casein, wherein crosslinks between casein macromolecules have been obtained by abstracting hydrogen atoms from the casein macromolecules by means of free radicals, the cross-linked polymeric material being a substantially rigid material that is mechanically workable by cutting, milling, turning and drilling.
number: 14
text: Cross-linked polymeric material according to claim 13, wherein further crosslinks between casein macromolecules have been obtained through reactions with at least one epoxide compound having at least two epoxide groups.
number: 15
text: An article, in particular a button (70) for an item of clothing, wherein the article is made of the cross-linked polymeric material according to any of claims 12 to 14.
Office action: search_report, dated 2020-12-23
Rejection reasons: novelty_epc_54
Prior art cited: ref_id: GB191424742A
ref_type: patent
severity: background
ref_id: GB191501221A
ref_type: patent
severity: background
ref_id: GB224672A
ref_type: patent
severity: background
ref_id: GB259418A
ref_type: patent
severity: background
ref_id: GB224672A
ref_type: patent
severity: background
ref_id: GB259418A
ref_type: patent
severity: background
ref_id: GB630150A
ref_type: patent
severity: background
ref_id: CN107446094A
ref_type: patent
severity: background
ref_id: GB224672
ref_type: patent
severity: novelty_destroying
ref_id: GB259418
ref_type: patent
severity: novelty_destroying
ref_id: GB630150
ref_type: patent
severity: novelty_destroying
Final disposition: pending (2020-12-23)