Method of treating a metal substrate

Patent metadata

Field	Value
Publication number	US-2016251602-A1
Application number	US-201414902506-A
Country	US
Kind code	A1
Filing date	Mar 3, 2014
Priority date	Jul 5, 2013
Publication date	Sep 1, 2016
Grant date	—

Abstract

A method of cleaning a metal substrate, the method comprising exposing the metal substrate to a body of cleaning liquor comprising a cleaning formulation and a multiplicity of solid particles wherein the method further comprises causing the solid particles and the metal substrate to enter into contacting relative movement; wherein i) the cleaning formulation comprises at least one acid which has a pKa greater than about −1.7; and/or ii) the cleaning formulation comprises at least one base which has a pKb greater than about −1.7; and the length of the particles is from about 0.5 mm to about 6 mm.

First claim

1 . A method of cleaning a metal substrate, the method comprising exposing the metal substrate to a body of cleaning liquor comprising a cleaning formulation and a multiplicity of solid particles wherein the method further comprises causing the solid particles and the metal substrate to enter into contacting relative movement; wherein
i) the cleaning formulation comprises at least one acid which has a pKa greater than about −1.7; and/or ii) the cleaning formulation comprises at least one base which has a pKb greater than about −1.7; and the length of the particles is from about 0.5 mm to about 6 mm.

2 . The method according to claim 1 wherein the cleaning formulation comprises a solvent.

3 . The method according to claim 1 or claim 2 wherein the cleaning formulation comprises at least one surfactant.

4 . The method according to claim 3 wherein the at least one surfactant is a non-ionic surfactant.

5 . The method according to any one of the preceding claims wherein the cleaning formulation comprises at least one acid which has a pKa greater than about −1.7.

6 . The method according to claim 5 wherein the at least one acid has a pKa between about −1.7 and about 15.7.

7 . The method according to claim 5 or claim 6 wherein the at least one acid is an organic acid.

8 . The method according to any one of the preceding claims wherein the cleaning formulation comprises at least one base which has a pKb greater than about −1.7.

9 . The method according to claim 8 wherein the at least one base has a pKb between about −1.7 and about 15.7.

10 . The method according to any one of the preceding claims wherein the cleaning formulation comprises a compound with at least one carboxylic acid moiety.

11 . The method according to any one of the preceding claims wherein the cleaning formulation comprises a compound with two or more carboxylic acid moieties.

12 . The method according to any one of the preceding claims wherein the cleaning formulation comprises a compound containing at least one citrate moiety.

13 . The method according to any one of the preceding claims wherein the cleaning formulation comprises at least one metal chelating agent.

14 . The method according to any one of the preceding claims wherein the cleaning formulation is aqueous.

15 . The method according to any one of the preceding claims wherein the cleaning formulation has a pH between about 1 and about 13.

16 . The method according to any one of the preceding claims wherein the cleaning formulation has a pH greater than about 7.

17 . The method according to any one of the preceding claims wherein at least some of the solid particles are buoyant in the cleaning formulation.

18 . The method according to any one of the preceding claims wherein the solid particles have an average density of less than about 1.

19 . The method according to any one of the preceding claims wherein the solid particles are in the form of beads.

20 . The method according to any one of the preceding claims wherein the method comprises moving the metal substrate such that its surface is brought into contact with the solid particles.

21 . The method according to any one of the preceding claims wherein the method comprises rotating, oscillating or reciprocating the metal substrate within the cleaning liquor.

22 . The method according to any one of the preceding claims wherein the method comprises scouring the surface of the metal substrate with the solid particles.

23 . The method according to any one of the preceding claims wherein the method comprises agitating the solid particles within the cleaning liquor.

24 . The method according to any one of the preceding claims wherein the method is carried out using a fluidized bed containing the cleaning liquor.

25 . The method according to any one of the preceding claims wherein the cleaning liquor contacts the metal surface at a relative velocity of at least 1 cm per second.

26 . The method according to any one of the preceding claims wherein the multiplicity of solid particles comprises or consists of a multiplicity of polymeric particles or wherein the multiplicity of solid particles comprises or consists of a multiplicity of non-polymeric particles.

27 . The method according to any one of the preceding claims wherein the multiplicity of solid particles comprises or consists of a mixture of a multiplicity of polymeric particles and a multiplicity of non-polymeric particles.

28 . The method according to any one of the preceding claims wherein the multiplicity of solid particles comprises or consists of a multiplicity of polymeric particles.

29 . The method according to any of claims 26 to 28 wherein the polymeric particles comprise particles of one or more polar polymers.

30 . The method according to any of claims 26 to 28 wherein the polymeric particles comprise particles of one or more non-polar polymers.

31 . The method according to any of claims 26 to 28 wherein the polymeric particles comprise particles of one or more polar polymers and particles of one or more non-polar polymers.

32 . The method according to any of claims 26 to 31 wherein the polymeric particles comprise particles selected from particles of polyalkenes, polyamides, polyesters, polysiloxanes, polyurethanes or copolymers thereof.

33 . The method according to any of claims 26 to 28 or any of claims 30 to 32 wherein the polymeric particles comprise particles selected from particles of polyalkenes or copolymers thereof.

34 . The method according to claim 33 wherein the polymeric particles comprise particles of polypropylene.

35 . The method according to any of claims 26 to 29 , claim 31 or claim 32 wherein the polymeric particles comprise particles selected from polyamide, polyester or copolymers thereof.

36 . The method according to claim 35 wherein the polyamide particles comprise particles of nylon.

37 . The method according to claim 35 wherein the polyester particles comprise particles of polyethylene terephthalate or polybutylene terephthalate.

38 . The method according to claim 26 or 27 wherein the non-polymeric particles comprise particles of ceramic material, refractory material, igneous, sedimentary, metamorphic minerals or composites.

39 . The method according to any of claims 26 to 37 wherein the polymeric particles comprise particles selected from linear, branched or cross-linked polymers.

40 . The method according to any of claims 26 to 37 and claim 39 wherein the polymeric particles comprise foamed or unfoamed polymers.

41 . The method according to any one of the preceding claims wherein the solid particles are of hollow and/or porous construction.

42 . The method according to any of claims 26 to 37 or claims 39 and 40 wherein the polymeric particles have an average density of from about 0.5 to about 3.5 g/cm 3 .

43 . The method according to claim 26 , 27 or 38 , wherein the non-polymeric particles have an average density of from about 3.5 to about 12.0 g/cm 3 .

44 . The method accordi

Assignees

• Xeros Ltd

Inventors

• Steele John Edward
• Bird Robert Andrew

Classifications

• C11D3/3749

  Polyolefins; Halogenated polyolefins; Natural or synthetic rubber; Polyarylolefins or halogenated polyarylolefins · CPC title

• B08B7/00

  Cleaning by methods not provided for in a single other subclass or a single group in this subclass · CPC title

• C11D3/2086

  Hydroxy carboxylic acids-salts thereof · CPC title

• B24C1/00

  Methods for use of abrasive blasting for producing particular effects; Use of auxiliary equipment in connection with such methods · CPC title

• B08B3/08

  the liquid having chemical or dissolving effect · CPC title