Treatment of raw animal hides and skins

• US 5,096,553 A
• Filed: 02/13/1990
• Issued: 03/17/1992
• Est. Priority Date: 09/11/1986
• Status: Expired due to Term

• Current Assignee: Ionizing Energy Company of Canada Limited
• Original Assignee: Ionizing Energy Company of Canada Limited
• Inventors: Herer, Arnold S., Ross, Graeme D.
• Primary Examiner(s): Tung, T.
• Assistant Examiner(s): Ryser, David G.
• Application Number:
  US07/480,339
• Time in Patent Office: 763 Days
• Field of Search: 204/157.15, 204/135, 422/22, 422/28, 8/94.1 R, 8/94.15
• US Class Current: 204/157.15
• CPC Class Codes: C14C 1/02 Curing raw hides

Abstract

There is described a new and improved method of treating raw animal hides and skins prior to tanning, wherein the hides and skins are initially washed, trimmed, fleshed and demanured, including the steps of dipping the hides and skins in a dilute antiseptic solution for a predetermined amount of time, removing excess moisture from the hides and skins following dipping, and irradiating the hides and skins with substantially monodirectional electron beams to expose each hide and skin to a dose adjustable within the range of 0.75 to 4.0 Mrads at a dose rate adjustable within the range of 10⁵ to 10⁷ rads/sec.

Claims

1. A method of treating raw animal hides and skins prior to tanning, wherein the hides and skins are initially washed, trimmed, fleshed and demanured, comprising the steps of:

a) dipping said hides and skins in a dilute antiseptic solution for a predetermined amount of time;

b) removing excess moisture from said hides and skins following said dipping; and

c) irradiating said partially dried hides and skins with substantially nondirectional electron beams to expose each such hide and skin to a dose adjustable within the range of 0.75 to 4.0 Mrads at a dose rate adjustable within the range of 10⁵ to 10⁷ rads/sec.

2. The method of claim 1 wherein the duration of said dipping is within the range of 1 to 60 minutes depending upon the nature and characteristics of the dipped skins and hides.

3. The method of claim 1 wherein said skins and hides are conveyed individually through a flux of said electron beams at a linear speed adjustable within the range of 20 to 120 linear feet per minute.

4. The method of claim 1 wherein the said dose is adjustable within the range substantially between 1.6 and 3.2 Mrads.

5. The method of claim 1 wherein the concentration of antiseptic is variable within the range 50 to 1000 PPM, Depending upon the antiseptic used.

6. The method of claim 1 wherein the energy of said electron beam radiation is within the range of 2 to 5 MeV.

7. The method of claim 1 including the additional step of partially drying the skins and hides a second time following said irradiation thereof.

8. The method of claim 7 wherein said skins and hides are retreated with antiseptic following irradiation thereof.

9. The method of claim 1 including the additional step of packaging said treated skins and hides under substantially antiseptic conditions to improve preservation times.

10. The method of claim 1 wherein said partially dried skins and hides are individually pre-bagged prior to being irradiated.

16. The method of claim 1 wherein the energy of said electron beam is within the range of 2 MeV to 5 MeV.

17. The method of claim 16 wherein said hides and skins are packaged prior to being irradiated.

18. The method of claim 17 wherein said hides and skins are conveyed individually through said flux of electron beams at a linear speed adjustable within the range of 20 to 120 linear feet per minute.

19. The method of claim 18 wherein the concentration of antiseptic is variable within the range of 50 to 1,000 PPM depending upon the antiseptic used.

20. The method of claim 19 wherein said irradiated hides and skins are dried a second time following irradiation.

21. The method of claim 20 wherein said skins and hides are retreated with antiseptic following irradiation thereof.

11. An industrial scale method of preserving a plurality of raw hides and skins prior to an additional treatment thereof to produce leather and related stable products, comprising the steps of:

a) washing, trimming, fleshing and demanuring said raw hides and skins;

b) dipping said hides and skins in dilute antiseptic;

c) partially drying said hides and skins to remove excess moisture therefrom;

d) individually pre-packaging said partially dried hides and skins;

e) arranging said pre-packaged hides and skins in an extended, substantially flat condition on conveyor means;

f) moving said hides and skins through a flux of high energy electron beam radiation to irradiate one side of said hides and skins at a dose adjustable within the range of 0.8 to 2.8 Mrads and at a dose rate adjustable within the range of 10⁵ to 10⁷ rads/sec.; and

g) irradiating the side of said hides and skins opposite to said one side thereof at a dose adjustable within the range of 0.8 to 2.8 Mrads at a dose rate adjustable within the range of 10⁵ to 10⁷ rads/sec.

12. The method of claim 11 wherein said skins and hides are bathed in said dilute antiseptic dip for a period of between 1 to 60 minutes.

13. The method of claim 12 wherein the energy of said electron beam is within the range of 2 MeV to 5 MeV.

14. The method of claim 13 wherein said skins and hides are conveyed individually through a flux of said electron beams at a linear speed adjustable within the range of 20 to 120 linear feet per minute.

15. A method of treating raw animal hides and skins prior to tanning, wherein the hides and skins are initially washed, trimmed, fleshed and demanured, comprising the steps of:

a) dipping said hides and skins in a dilute antiseptic solution for a period of between 1 and 60 ll minutes;

b) removing excess moisture from said hides and skins following said dipping;

c) arranging said hides and skins in an unfolded subtantially flat condition on conveyor means;

d) moving said hides and skins through a flus of high energy electron beam radiation to irradiate one said of said hides and skins at a dose adjustable within the range of 0.8 to 2.8 Mrads at a dose rate adjustable within the range of 10⁵ to 10⁷ rads/sec; and

e) irradiating the side of said hides and skins opposite to said one side thereof at a dose adjustable within the range of 0.8 to 2.8 Mrads at a dose rate adjustable within the range of 10⁵ to 10⁷ rads/sec.