U.S. patent application number 10/877076 was filed with the patent office on 2004-11-25 for conveyor lubricant with corrosion inhibition.
This patent application is currently assigned to Ecolab Inc.. Invention is credited to Lawrence, Michel, Wichmann, Gerald.
Application Number | 20040235680 10/877076 |
Document ID | / |
Family ID | 33456466 |
Filed Date | 2004-11-25 |
United States Patent
Application |
20040235680 |
Kind Code |
A1 |
Lawrence, Michel ; et
al. |
November 25, 2004 |
Conveyor lubricant with corrosion inhibition
Abstract
A lubricant composition which protects polymeric articles, and
which also inhibits corrosion of metal, the composition including
at least one oxyalkylated alcohol carboxylatic acid or salt
thereof, and methods of using the same. The composition is
advantageous where hydrogen peroxide is also present.
Inventors: |
Lawrence, Michel; (Inver
Grove Heights, MN) ; Wichmann, Gerald; (Maple Grove,
MN) |
Correspondence
Address: |
VIDAS, ARRETT & STEINKRAUS, P.A.
6109 BLUE CIRCLE DRIVE
SUITE 2000
MINNETONKA
MN
55343-9185
US
|
Assignee: |
Ecolab Inc.
St. Paul
MN
|
Family ID: |
33456466 |
Appl. No.: |
10/877076 |
Filed: |
June 24, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10877076 |
Jun 24, 2004 |
|
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10664265 |
Sep 17, 2003 |
|
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60411937 |
Sep 18, 2002 |
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Current U.S.
Class: |
508/175 ;
508/510; 508/517; 508/539; 508/579 |
Current CPC
Class: |
C11D 1/08 20130101; C11D
3/3947 20130101; C11D 11/0029 20130101; C11D 3/0073 20130101; C11D
1/06 20130101 |
Class at
Publication: |
508/175 ;
508/517; 508/539; 508/579; 508/510 |
International
Class: |
C10M 173/02 |
Claims
1. A composition comprising at least one oxalkylated alcohol
carboxylic acid or salt thereof, wherein said composition inhibits
the corrosion of metal in the presence of hydrogen peroxide.
2. The composition of claim 1 wherein said metal is cold rolled
steel or stainless steel.
3. The composition of claim 2 wherein said metal exhibits less than
0.2% weight loss upon exposure to said composition.
4. The composition of claim 1, said composition comprising about 1
wt-% to about 10 wt-% hydrogen peroxide.
5. The composition of claim 1, said composition comprising about 1
wt-% to about 5 wt-% hydrogen peroxide.
6. The composition of claim 1, said composition comprising about 1
wt-% to about 15 wt-% of said oxalkylated alcohol carboxylic acid
or salt thereof.
7. The composition of claim 1, said composition comprising about 1
wt-% to about 10 wt-% of said oxalkylated alcohol carboxylic acid
or salt thereof.
8. The composition of claim 1 diluted between about 1:200 to about
1:1000 of said composition to water.
9. The composition of claim 1 diluted between about 1:600 to about
1:800 of said composition to water.
10. The composition of claim 1 wherein hydrogen peroxide is added
to said composition.
11. The composition of claim 1 further comprising at least one of
sodium hydroxide or potassium hydroxide.
12. The composition of claim 1 further comprising at least one
member selected from the group consisting of pH adjusters or other
neutralizing agents, surfactants, emulsifiers, sequestrants,
solubilizers, other lubricants, buffers, detergents, bleaching or
decolorizing agents, antioxidants, preservatives, antistatic
agents, binders, thickeners or other viscosity modifiers,
processing aids, carriers, water-conditioning agents, antimicrobial
agents, foam inhibitors or foam generators, film formers and
combinations thereof.
13. The composition of claim 1 further comprising at least one
lubricant selected from the group consisting of amines, nonionic
surfactants, phosphate esters, silicones, and mixtures thereof.
14. The composition of claim 1 further comprising at least one
lubricant is an ethylene oxide/propylene oxide block copolymer.
15. The composition of claim 1 wherein said at least one lubricant
is oleic acid or a salt thereof.
16. A composition comprising at least one oxalkylated alcohol
carboxylic acid or salt thereof, said composition inhibits the
corrosion of metal in the presence of hydrogen peroxide.
17. The composition of claim 16 wherein said metal is cold rolled
steel or stainless steel.
18. The composition of claim 17 wherein said metal loses less than
about 0.2% of its weight in the presence of hydrogen peroxide.
19. The composition of claim 16 wherein said hydrogen peroxide is
present from about 1 wt-% to about 10 wt-%.
20. The composition of claim 16 wherein said oxalkylated alcohol
carboxylic acid or salt thereof is present at a concentration of
about 1 wt-% to about 15 wt-%.
21. The composition of claim 16 further diluted between about 1:200
to about 1:1000 of said composition to water.
22. The composition of claim 16 further diluted between about 1:600
to about 1:800 of said composition to water.
23. A lubricant composition for containers and/or conveyors
comprising an effective amount of at least one lubricant and at
least one oxyalkylated alcohol carboxylic acid or salt thereof.
24. The lubricant composition of claim 23 further comprising
hydrogen peroxide.
25. The lubricant composition of claim 23 wherein said at least one
lubricant is selected from the group consisting of fatty amines,
nonionic surfactants, phosphate esters, silicones, and mixtures
thereof.
26. The lubricant composition of claim 23 further comprising at
least one lubricant which is an ethylene oxide/propylene oxide
block copolymer.
27. The lubricant composition of claim 23 wherein said at least one
lubricant is oleic acid or a salt thereof.
28. The composition of claim 23 wherein said oxyalkylated alcohol
carboxylic acid or salt thereof is an ethoxylated alcohol
dicarboxylic acid.
29. The composition of claim 23 comprising about 1 wt-% to about 15
wt-% of said oxalkylated alcohol carboxylic acid or salt
thereof.
30. The composition of claim 23 further diluted at a ratio between
about 1:200 to about 1:1000 of said composition to water.
31. The composition of claim 23 further diluted at a ratio of about
1:600 to about 1:800 of said composition to water.
32. The composition of claim 23 wherein said composition inhibits
corrosion of metal in the presence of hydrogen peroxide
33. The composition of claim 32 wherein the metal is cold rolled
steel or stainless steel.
34. The composition of claim 33 wherein said metal exhibits a
weight loss of less than 0.2 wt-% based on initial weight before
exposure to hydrogen peroxide.
35. The composition of claim 23 said composition having a pH
greater than 7.
36. The composition of claim 23 further comprising at least one
member selected from the group consisting of pH adjusters or other
neutralizing agents, surfactants, emulsifiers, sequestrants,
solubilizers, other lubricants, buffers, detergents, bleaching or
decolorizing agents, antioxidants, preservatives, antistatic
agents, binders, thickeners or other viscosity modifiers,
processing aids, carriers, water-conditioning agents, antimicrobial
agents, foam inhibitors or foam generators, film formers and
combinations thereof.
37. The composition of claim 23 further comprising about 1 wt-% to
about 90 wt-% water.
38. The composition of claim 23 further comprising about 50 wt-% to
about 85 wt-% water.
39. A method of lubricating the interface between a container and a
moving conveyor surface, the method comprising: (a) applying an
aqueous lubricant composition to the container, the conveyor or
both, the lubricant comprising an effective amount of at least one
lubricant and at least one oxalkylated alcohol carboxylic acid or
salt thereof; and (b) moving the container on the conveyor surface
in order to transport the container from a first location to a
second location.
40. The method of claim 40 wherein said lubricant has a pH greater
than 7.
41. The method of claim 40 wherein said lubricant is effective in
an alkaline environment of about 200 ppm alkalinity.
42. The method of claim 40 wherein said container is a liquid
beverage container.
43. The method of claim 42 wherein said beverage container is
filled with said liquid beverage.
44. The method of claim 42 wherein said beverage container is
polyolefin, polyester, polycarbonate, PVC or copolymers
thereof.
45. The method of claim 40 wherein said composition inhibits
corrosion of metal.
46. The method of claim 40 wherein said lubricant composition
further comprises hydrogen peroxide.
47. The method of claim 45 wherein said metal is cold rolled steel
or stainless steel.
48. The method of claim 40 wherein said composition exhibits
protection of polymeric articles.
49. The method of claim 48 wherein said polymeric articles are
formed from polyester, polyolefins, polycarbonates, copolymers
thereof and mixtures thereof.
50. The method of claim 49 wherein said polymeric articles are
formed from polyethylene terephthalate or polybutylene
terephthalate.
51. The method of claim 48 wherein said polymeric articles exhibit
minimal stress cracking or hazing.
52. A method of protecting a polymeric article of manufacture by
coating at least a portion of the surface of said polymeric article
with a lubricating composition, said composition comprising an
effective amount of at least one lubricant and at least one
oxalkylated alcohol carboxylic acid or salt thereof.
53. The method of claim 52 wherein said polymeric article is formed
from at least one member selected from the group consisting of
polyolefins, polyesters, polycarbonates, copolymers thereof and
mixtures thereof.
54. The method of claim 53 wherein said polymeric article is formed
form polyethylene terephthalate or polybutylene terephthalate.
55. The method of claim 52 wherein said polymeric article is a
beverage container.
56. The method of claim 52 wherein said lubricating composition
comprises about 1 wt-% to about 15 wt-% of said oxalkylated alcohol
carboxylic acid or salt thereof.
57. The method of claim 52 wherein said lubrication composition
comprises about 1 wt-% to about 10 wt-% of said oxalkylated alcohol
carboxylic acid or salt thereof.
58. The method of claim 52 wherein said oxalkylated alcohol
carboxylate is an ethoxylated alcohol dicarboxylic acid or salt
thereof.
59. The method of claim 52 wherein said lubricating composition
further comprises about 1 wt-% to about 90 wt-% water.
60. The method of claim 52 wherein said lubricating composition
further comprises about 50 wt-% to about 85 wt-% water.
61. The method of claim 52 wherein said lubricating composition is
further diluted at a ratio of about 1:200 to about 1:1000 of said
composition to water.
62. The method of claim 52 wherein said lubricating composition is
further diluted at a ratio of about 1:600 to about 1:800 of said
composition to water.
63. The method of claim 52 wherein said composition further
comprises hydrogen peroxide.
Description
CROSS-REFERENCE TO RELATED U.S. PATENT APPLICATIONS
[0001] This is a continuation-in-part of U.S. patent application
Ser. No. 10/664265 filed Sep. 17, 2003 which claims the benefit of
U.S. Provisional Patent Application Ser. No. 60/411937 filed Sep.
18, 2002.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to conveyor lubricant
compositions and to methods of using the same.
[0003] In commercial container filling or packaging operations, the
containers typically are moved by a conveying system at very high
rates of speed. In most packaging operations, the containers are
moved along conveying systems, usually in an upright position, with
the opening of the container facing vertically up or down. The
containers are moved from station to station where various
operations are performed including, for example, filling, capping,
labeling, sealing, and so forth. In a beverage operation in
particular, it is important that the containers move without
hindrance along the conveyor such that no liquid is spilled onto
the conveyor during the times when the containers are open. This is
especially important for dairy based beverages such as milk because
milk can coagulate on the equipment surfaces. Lubricants are thus
commonly used to ensure the appropriate movement of the containers
on the conveyor.
[0004] Lubricant compositions are used on conveying systems in the
beverage industry during the filling of containers with dairy
products or other beverages. The conveyor systems are typically
lubricated to reduce friction between the package and the load
bearing surface of the conveyor. These lubricants are typically
applied to the conveyor belts and/or the containers to reduce
friction between the container and the conveyor. This facilitates
unhindered conveyance of bottles on the conveyor belt. These
lubricants may also be referred to as chain conveyor or belt
lubricants.
[0005] Good lubricating properties are not the only important
considerations when selecting a lubricant for use in the beverage
bottling industry. Another consideration is that the lubricant be
compatible with the beverage such that it does not form coagulates
or other solid deposits when it accidentally contacts spilled
beverages on the conveyor system. Formation of such deposits on a
conveyor can change the lubricity of the conveyor and require
shutdown to permit cleanup. The lubricant must also be readily
cleaned from the equipment.
[0006] In the commercial distribution of most beverages, the
beverages are packaged in containers of varying sizes, such
containers being in the form of cartons, cans, bottles, tetrapack
packages, waxed carton packs, and other forms of containers. The
containers, in addition to their many possible formats and
constructions, may comprise many different types of materials, such
as metals, glasses, ceramics, papers, treated papers, waxed papers,
composites, layered structures, and polymeric materials.
[0007] Polymeric materials are commonly used in the beverage
industry. Examples of commonly used polymeric materials include,
polyolefins such as polyethylene, polypropylene, polystyrene,
copolymers thereof; polyesters and copolymers thereof such as
polyethyleneterephthalate and polyethylenenaphthalate; polyamides
and copolymers thereof; polycarbonates and copolymers thereof; and
so forth and mixtures thereof. Some aqueous conveyor lubricants are
incompatible with thermoplastic beverage containers made of
polyethylene terephthalate (PET) and other plastics, for example,
and can cause stress cracking (crazing and cracking that occurs
when the plastic polymer is under tension) in carbonated beverage
filled plastic containers.
[0008] There remains a need in the industry for an alternative to
currently available lubricants for containers and conveyors that
overcomes one or more of the disadvantages of currently used
lubricants.
SUMMARY OF THE INVENTION
[0009] The present invention relates to a lubricant composition
that reduces the coefficient of friction of coated conveyor parts
and containers and thereby facilitates movement of containers along
a conveyor line, and to methods of making and using the same.
[0010] The present invention relates to lubricants with additives
that provide improved corrosion resistance to metals as well as
protection to polymeric containers against stress cracking and
hazing.
[0011] The compositions according to the invention include at least
one corrosion inhibitor which is an oxyalkylated alcohol carboxylic
acid or salt thereof, suitably an oxalkylated alcohol dicarboxylic
acid or salt thereof. In one embodiment, the oxalkylated alcohol
carboxylate is an ethoxylated linear alcohol carboxylic acid or
salt thereof. These compounds may also be referred to in the art as
polycarboxylated alkylene oxide condensates of fatty alcohols.
[0012] A specific example is POLYTERGENT.RTM. CS1 available from
BASF which is an ethoxylated linear alcohol carboxylic acid.
[0013] The oxalkylated linear alcohol carboxylic acid or salt
thereof, such as POLYTERGENT.RTM. CS1, may be represented by the
following general formula: 1
[0014] R is a typical surfactant hydrophobe, X and Y are
independently H, CH.sub.3 or a succinic acid radical. For example,
R may be a hydrocarbon group having from about 8 to about 20 carbon
atoms, more typically about 9 to about 16 carbon atoms.
[0015] Other useful dicarboxylic acids, triacarboxylic acids, and
so forth useful herein are described in commonly assigned U.S.
patent application Ser. No. 5,723,418, which is hereby incorporated
by reference in its entirety. One example is SOKALAN.RTM. DCS, a
mixture of adipic, glutaric and succinic acids, available from
BASF.
[0016] The oxalkylated alcohol carboxylatic acid or salt thereof is
useful in amounts of less than 20 wt-%, more suitably about 1 wt-%
to about 15 wt-% and most suitably about 1 wt-% to about 10 wt-% of
the composition.
[0017] The compositions further include an effective amount of at
least one lubricant. The present invention is not limited by the
type of lubricant employed herein, and any lubricant known in the
art may be used. Examples of suitable lubricants include, but are
not limited to, amines including amine acetates, primary, secondary
and tertiary amines, diamines, and fatty amines; phosphate esters;
anionic surfactants, cationic surfactants; nonionic surfactants
including ethylene oxide/propylene oxide block copolymers;
silicones including polymers, oils, and emulsions thereof; and so
forth.
[0018] As used herein, the term block copolymer, shall be used to
refer to diblocks, triblocks and so forth.
[0019] The lubricant compositions used in the invention may contain
water or a hydrophilic diluent, as a component or components in the
lubricant composition as sold or added just prior to use.
[0020] The compositions may be diluted with water at the time of
use at a ratio of about 1:200 to about 1:1000, suitably about 1:600
to about 1:800 of the composition to water.
[0021] The compositions exhibit excellent corrosion inhibition for
metals in the presence of hydrogen peroxide. Hydrogen peroxide may
be employed in a variety of different types of compositions for a
variety of different reasons, including, but not limited to,
cleaning booster in hot caustic cleaning solutions, in dilute
lubricant compositions as a biocide, as a bleaching agent, for the
destruction of bleach, and so forth. When used in alkaline cleaning
solutions, peroxide is added as an adjunct chemical additive.
Peroxide is not stable in solutions with a higher pH. It is
effective as a booster for the removal of baked-on and carbonized
soil. It may also be used to produce alkylamine oxide surfactants
from alkylamines. It is, however, corrosive to metal such as steel.
The additives according to the invention may be added to
compositions, wherein hydrogen peroxide is employed, to inhibit the
corrosion of metal.
[0022] Other aspects and advantages will become clear from the
following Detailed Description.
DETAILED DESCRIPTIONS OF THE INVENTION
[0023] While this invention may be embodied in many different
forms, there are described in detail herein specific embodiments of
the invention. This description is an exemplification of the
principles of the invention and is not intended to limit the
invention to the particular embodiments illustrated.
[0024] The additive for inhibiting corrosion of metals includes at
least one oxalkylated alcohol carboxylic acid or salt thereof.
These compounds are also referred to in the art as polycarboxylated
alkylene oxide condensates of fatty alcohols.
[0025] Oxalkylated alcohol carboxylic acids or salts thereof may be
represented by the following general formula: 2
[0026] R is a typical surfactant hydrophobe, X and Y are
independently H, CH.sub.3 or a succinic acid radical. For example,
R may be a hydrocarbon group having from about 8 to about 20 carbon
atoms, more typically about 9 to about 16 carbon atoms.
[0027] A specific example is POLYTERGENT.RTM. CS1 which is an
ethoxylated linear alcohol dicarboxylic acid available from BASF
Corp.
[0028] The oxalkylated alcohol carboxylic acid or salt thereof may
be used in amounts of less than about 20 wt-%, more suitably about
1 wt-% to about 15 wt-% and most suitably about 1 wt-% to about 10
wt-% of the composition.
[0029] Any lubricants known in the art may find utility in the
compositions of the present invention and including synthetic
lubricants such as silicones, glycerin, petroleum based lubricants
such as mineral oil, and natural lubricants including fatty oils
and animal and vegetable oils including those which are edible.
[0030] Lubricants may be natural or synthetic, and come in a
variety of classes including, for example, amines, cationic,
anionic and nonionic surfactants, phosphate esters, silicones, and
so forth. Acids may come in a form which has been neutralized with
a base such as potassium or sodium hydroxide.
[0031] More specific examples include, but are not limited to,
synthetic hydrocarbons; organic esters; high molecular weight
alcohols; perfluoroalkylpolyethers (PFPE); silicates; silicones
including polymers, oils and emulsions thereof; fluoropolymers such
as chlorotrifluoroethylene; polyphenyl ethers; poly(alkylene)
glycol(s) including polyethylene and polypropylene glycols;
oxypolyalkylene glycols; copolymers of ethylene and propylene
oxide, polyhydroxy compounds; ethoxylated amines; primary,
secondary and tertiary amines; alkanolamines; fatty acid amines
including N-coco B-Amino propionic acid amphoteric surfactant;
perfluoroalkylpolyethers (PFPE); polyhydroxy compounds; and so
forth and mixtures thereof. This list is intended for illustrative
purposes only, and is not intended to limit the scope of the
present invention.
[0032] The ethylene oxide/propylene oxide block copolymers
including triblock copolymers having the following general formulas
find utility herein:
(EO).sub.x(PO).sub.y(PO).sub.z
[0033] wherein EO represents ethylene oxide residue, PO represents
propylene oxide residue, and x, y, and z equal independently
selected integers from about 2 to 100. These lubricants are
available from BASF under the tradename of PLURONIC.RTM. and
include PLURONIC.RTM. 10R5 and PLURONIC.RTM. G F108 which is an
EO-PO-EO triblock polymer.
[0034] Another example of suitable lubricants are the ethoxylated
alcohols. A specific example is TOMADOL.RTM. 45-13, an alcohol
ethoxylate that includes a 14-15 carbon alcohol with 13 moles
ethylene oxide. This is available from Tomah Products, Inc. in
Milton, Wis.
[0035] Another specific example are the alkyl polyglucosides
available from Cognis North America in Cincinnati, Ohio under the
tradename of GLUCOPON.RTM. including GLUCOPON.RTM. 220, 225, 425,
600 and 625.
[0036] Other specific examples of useful lubricants include fatty
acids or salts thereof such as oleic acid, corn oil, mineral oil
available from Vulcan Oil and Chemical Products under the
Bacchus.RTM. trademark; fluorinated oils and fluorinated greases,
available from DuPont in Wilmington, Del. under the trademark
Krytox.RTM.; siloxane fluids available from General Electric
silicones, such as SF96-5 and SF 1147 and other silicone emulsions;
synthetic oils and their mixture with PTFE available from Synco
Chemical under the trademark Super Lube.RTM.; polyalkylene glycols
from Union Carbide such as UCON.RTM. LB625 and CARBOWAX.RTM. 300;
block copolymer surfactants such as UCON.RTM. 50HB660 ethylene
oxide(EO)/propylene oxide (PO) monobutyl ether; and so on and so
forth.
[0037] Lubricants are available in solid form as well. Examples
include, but are not limited to, molybdenum disulfide, boron
nitride, graphite, silica particles, silicone gums and particles,
polytetrafluoroethylene (PTFE, Teflon), fluoroethylene-propylene
copolymers (FEP), perfluoroalkoxy resins (PFA),
ethylene-chloro-trifluoroethylene alternating copolymers (ECTFE),
poly (vinylidene fluoride) (PVDF), and the like. The lubricant
composition can also contain a solid lubricant as a suspension in a
substantially aqueous or non-aqueous liquid.
[0038] Lubricants are useful from about 1 wt-% to about 20 wt-% of
the composition, suitably about 1 wt-% to about 10 wt-%.
[0039] The above lists are not exhaustive, and are intended for
illustrative purposes only, and not as a limitation on the scope of
the present invention. One of ordinary skill in the art has
knowledge of such lubricants. Suitable lubricants are described,
for example, in commonly assigned U.S. Pat. Nos. 6,576,298,
5,925,610, 5,559,087 and 5,352,376, each of which is incorporated
by reference herein in its entirety.
[0040] The lubricant compositions used in the invention may be
available as concentrates, or as diluted use solutions. As such,
the lubricant compositions may contain water or a hydrophilic
diluent, as a component or components in the lubricant composition
as sold or added just prior to use. Suitably, the lubricant
composition does not require in-line dilution with significant
amounts of water, that is, it can be applied with little or no
dilution.
[0041] Suitably, the lubricant compositions include about 1 wt-% to
about 90 wt-% water, and more suitably about 25 wt-% to about 85
wt-% and most suitably about 50 wt-% to about 85 wt-%. Of course,
such compositions can be further diluted during use.
[0042] The lubricant compositions may be diluted with water at a
ratio of about 1:200 to about 1:1000, suitably about 1:600 to about
1:800 of the composition to water.
[0043] A variety of other optional ingredients may be incorporated
into the compositions including, but not limited to, pH adjusters
such as potassium or sodium hydroxide or other neutralizing agents,
surfactants, emulsifiers, sequestrants, solubilizers, other
lubricants, buffers such as potassium carbonate, detergents,
bleaching or decolorizing agents, antioxidants, preservatives such
as methyl and/or propyl paraben, antistatic agents, binders,
thickeners or other viscosity modifiers, processing aids, carriers,
water-conditioning agents, antimicrobial agents, foam inhibitors or
foam generators, film formers, hydrotopes, also called coupling
agents, combinations thereof, and so forth. The amounts and types
of such additional components are apparent to those skilled in the
art.
[0044] The compositions according to the invention have also been
found to exhibit superior corrosion resistance, particularly
hydrogen peroxide-containing compositions when employing the
oxalkylated alcohol carboxylates as the protectant, and
particularly when lower grades of steel, such as cold rolled steel,
are exposed to such compositions. Hydrogen peroxide tends to
aggravate corrosion of lower grade steel such as cold rolled steel.
However, when exposed to the hydrogen peroxide-containing
compositions with the oxalkylated alcohol carboxylates as the
protectant, the cold rolled steel exhibited a weight loss of less
than 0.2 wt % and even less than 0.1 wt %. Based on a starting
weight of 23 g, the weight loss was about 5 mg, and even less than
2 mg, while prior compositions exhibited weight loss of as much as
>120 mg.
[0045] The lubricant compositions may be employed to lubricate the
interface between a moving conveyor and any work piece that is
moved along by the conveyor, and in particular for containers that
are moved from one location to another. Such a method involves
applying an aqueous liquid lubricant composition to the container,
the conveyor, or both. The lubricant comprising an effective amount
of at least one lubricant and at least one protectant and moving
the container on the conveyor surface in order to transport the
container from a first location to a second location.
[0046] The present invention is particularly advantageous where the
containers are filled with liquids prior to moving from one
location to another, wherein it is desirable that the liquids are
not spilled. For example, the lubricant composition can be used for
conveying a wide variety of containers including beverage
containers; food containers; household or commercial cleaning
product containers; and containers for oils, antifreeze or other
industrial fluids.
[0047] The containers can be made of a wide variety of materials
including glasses; polymeric materials such as polyolefins
including polyethylene and polypropylene and copolymers thereof;
polystyrenes and copolymers thereof; polyesters and copolymers
thereof such as PET and polyethylene naphthalate (PEN); polyamides
and copolymers thereof; polycarbonates and copolymers thereof; and
so on and so forth; metals including, for example aluminum, tin or
steel; papers including untreated, treated, waxed or other coated
papers or laminates thereof; ceramics; and laminates or composites
of two or more of these materials. The containers can have a
variety of sizes and forms, including cartons such as waxed
cartons. TETRAPACK.RTM. boxes, cans, bottles and the like.
[0048] The lubricant composition may be applied to the container
and/or conveyor using any suitable means known in the art. Although
any desired portion of the container can be coated with the
lubricant composition, the lubricant composition is suitably
applied only to parts of the container that will come into contact
with the conveyor or with other containers, and suitably, the
lubricant composition is not applied to parts that later come into
contact with a user who grips or holds the container, or, if so
applied, is preferably removed from such portion prior to shipment
and sale of the container. Application of the lubricant composition
to the conveyor, rather than the container, can alleviate problems
of slipperiness with the latter.
[0049] The surface of the conveyor that supports the containers may
comprise fabric, metal, plastic, elastomer, composites, or mixture
of these materials. Any type of conveyor system used in the field
can be treated according to the present invention. The lubricant
composition can be applied to a conveyor system surface that comes
into contact with containers, the container surface that needs
lubricity, or both. The lubricant composition can be applied in any
desired manner, for example, by spraying, wiping, rolling,
brushing, or a combination of any of these, to the conveyor surface
and/or the container surface. If the container surface is coated,
it is only necessary to coat the surfaces that come into contact
with the conveyor, and/or that come into contact with other
containers. Similarly, only portions of the conveyor that contacts
the containers need to be treated. Methods of application are
discussed in commonly assigned U.S. Pat. Nos. 6,576,298 and
6,495,494, for example, each of which is incorporated by reference
herein in its entirety.
[0050] A variety of kinds of conveyors and conveyor parts can be
coated with the lubricant composition. Parts of the conveyor that
support, guide, or move the containers are preferably coated with
the lubricant composition. These parts include belts, chains,
gates, chutes, sensors, and ramps having surfaces made of fabrics,
metals, plastics, composites, or combinations of these
materials.
[0051] The additives, according to the invention, find utility for
the protection of polymeric articles to prevent hazing and stress
cracking. This is especially a concern when the polymeric articles
are exposed to alkaline conditions.
[0052] The additives, according to the invention, also find utility
in any composition having hydrogen peroxide or under any
circumstances where metal such as steel comes into contact with
hydrogen peroxide. The additives, according to the invention, find
utility, not only in lubricant compositions, but in cleaning
compositions, particularly hot caustic cleaning compositions,
bleaches, and so forth. When used in alkaline cleaning solutions,
peroxide is added as an adjunct chemical additive. Peroxide becomes
less stable at a higher pH such as at those pH values of greater
than 7.
[0053] The following non-limiting examples further illustrate the
present inventive concepts.
EXAMPLES
[0054] Test Methods
[0055] 1. PET Stress Crack Test
[0056] Standard 2-liter PET beverage bottles (commercially
available from Constar International) were charged with 1850 g of
chilled water, 31.0 g of sodium bicarbonate and 31.0 g of citric
acid. The charged bottle was capped, rinsed with deionized water
and set on clean plastic liners or paper towels overnight. The
bottoms of 12 bottles were dipped in a 200 g sample of 0.5% lube
solution that was prepared using DI water with 200 ppm added
alkalinity. The bottles were then placed in a bin and 85.2 g of the
lube solution is evenly distributed to the bottom of the bin. The
bottles/bin were stored in an environmental chamber at 37.8.degree.
C., 90% relative humidity for 28 days. Burst bottles were tracked
throughout the test. At the end of the test the bottles were
removed from the chamber, observed for crazes, creases and crack
patterns on the bottom.
[0057] 2. Corrosion Test
[0058] The corrosion test is based on test method ASTM 3.02, G31-72
and 3.02 G1-90.
[0059] Coupons of cold rolled steel and stainless steel were
cleaned using Bon-Ami cleanser, rinsed with deionized water, rinsed
with acetone, and dried with canned air. The coupons were set in
wood drying racks overnight. Each coupon was then weighed on an
analytical balance to 0.1 mg. Each coupon originally weighed
approximately 23 g.
[0060] Approximately 215 grams of each test solution was added to 8
ounce glass bottles labeled to identify the solution inside. The
lubricant concentration was 0.5% for all solutions. The bottles
were capped and placed in an oven at 50.degree. C. overnight. One
coupon was added to each jar and the jars were capped. The capped
jars were returned to the oven at 50.degree. C. Each coupon type
was tested in triplicate for each solution type. The coupons were
visually inspected each day for corrosion without removing them
from the jars. The jars were left capped the entire testing period.
One of each coupon type was soaked in each solution type for 7 days
and two of each type of coupon were soaked in each solution type
for 14 days.
[0061] Post-cleaning of the cold rolled steel coupons included
rinsing each coupon after removal from the jar and then soaking
each coupon for 3 minutes at room temperature in a 100 mls of a
solution of 20 g of Sb2O3, 50 g of SnCl2 and 1000 mL HCl in a 150
mL beaker. Each coupon was then removed from the cleaning solution,
rinsed with deionized water, rinsed with acetone, and dried with
canned air. The coupons were then set in the wood drying racks and
were weighed when all coupons had been cleaned and dried.
[0062] Post-cleaning of the 316 stainless steel coupons included
rinsing each coupon after removal from the jar and then placing the
coupons in a stainless steel rack. The rack was then lowered into a
large beaker with a solution of 150 g diammonium citrate/liter
water. The beaker was then placed in an oven at 70.degree. C. for
20 minutes. After 20 minutes, the metal rack was removed from the
solution and each coupon was rinsed with deionized water, rinsed
with acetone, and dried with canned air. The coupons were then set
in the wood drying racks and were weighed when all coupons had been
cleaned. The weight loss was calculated for each coupon by
subtracting the final weight from the initial weight, and adjusting
the weight loss by adding back or by subtracting any weight
loss/gain that occurred during exposure of the coupons to air in
the oven. The air samples were used as blanks so that the only
weight loss/gain is due solely to corrosion in the test solutions
and is not due to weight loss/gain due to the post-cleaning
procedure.
1TABLE 1 Chemical Example 1 Comparative Comparative Description
(wt-%) Example A Example B Tomadol .RTM. C.sub.14-15 alcohol/13
5.00 5.00 5.00 45-13 (Tomah moles ethylene Products, Inc.) oxide;
lubricant Pluronic .RTM. EO-PO-EO 3.00 3.00 3.00 10R5 (BASF)
triblock polymer; lubricant Glucopon .RTM. Alkyl 1.00 1.00 1.00 625
(Cognis polyglucoside North America) surfactant; lubricant Hydrogen
cleaner 5.70 5.70 5.70 Peroxide; 35% Polytergent .RTM.
dicarboxylated 10.0 20.00 0 CS1; 50% ethoxylated (BASF) alcohol;
protectant DI Water 75.3 65.3 85.3
[0063] The amount of POLYTERGENT.RTM. CS1 was doubled from the
amount in example 1. This is comparative example A. Comparative
example B was prepared with no protectant. Example 1 and
comparative examples A and B were then tested using the PET Stress
Crack test described above. Example 1 exhibited only 1 failure in
24 total tests, comparative example A, at higher levels of
Polytergent.RTM. CS1, exhibited 5 failures and comparative example
B exhibited 4 failures out of 24.
[0064] A second example was prepared; the composition is found in
Table 3.
2TABLE 2 Chemical Description Example 2 Comp C Comp D Silicone
emulsion Lubricant 5.0 5.0 5.0 PLURONIC .RTM. EO-PO-EO 0.3 0.3 0.3
F108 (BASF) triblock polymer; lubricant Methyl Paraben Preservative
0.2 0.2 0.2 POLYTERGENT .RTM. dicarboxylated 10.0 20.0 0 CS1; 50%
(BASF) ethoxylated alcohol; protectant DI Water 84.5 74.5 94.5
[0065] The amount of POLYTERGENT.RTM. CS1 was increased by 10% from
the amount in example 2. This is comparative example C. Comparative
example D was prepared with no protectant. These formulas were also
tested according to the PET Stress Crack test described above.
Example 2 exhibited 1 failure out of 24, comparative example C
exhibited 6 failures out of 24 and comparative example D exhibited
4 failures out of 24.
[0066] The results are found in the following table 3.
3TABLE 3 Bottle Bottle Polytergent Bottle Grade Grade Overall CS1
Stress Test Craze Craze Bottle Weight-% #Failures/24 Depth Frequeny
Grade Example 1 10 1 1.13 1.5 3.63 Comparative 20 5 1.94 2 8.94 Ex
A Example 2 10 1 1.15 0.75 2.9 Comparative 20 6 2.23 1.5 9.73 Ex
C
[0067] A base formula was employed for preparing various
compositions which were then tested for corrosion inhibition of
metals. The base composition is also comparative example A and is
considered to be an industry standard. To the base formula, several
different compounds were added. The compositions as well as the
results of the testing are found in Table 4, below. The corrosion
resistance was tested using the test method described above.
[0068] The base composition was the following.
[0069] Base Composition (BC)=Comparative Example E
[0070] 5.0 wt-% Tomadol.RTM. 45-13; alcohol ethoxylate (Tomah
Products, Inc.)
[0071] 3.0 wt-% Pluronic.RTM. 10R5; ethylene oxide/propylene oxide
block copolymer (BASF)
[0072] 1.0 wt-% Glucopon.RTM. 625; alkyl polyglucoside (BASF)
[0073] 5.7 wt-% hydrogen peroxide, 35% active
[0074] 85.3 wt-% deionized water
[0075] Example 1 was compared to a variety of compositions for
corrosion to metal in the presence of hydrogen peroxide. The
compositions and results are summarized in Table 5 as follows:
4TABLE 4 CR 1018 CR 1018 316 SSCorrosion Corrosion Corrosion Wt
Loss Wt Loss Wt Loss Product (mg) (mg) (mg) % Comparative E Base
Composition 0 80 0.349 Comparative F Lubrodrive RX 0.025 32.6 0.145
Example 1 0.9 1.7 0.007 Comparative G BC + 10% Dowfax 8390 0.85*
50.2 0.218 Comparative H BC + 20% LBA 0.8 54.85 0.239 Comparative I
BC + 10% Avanel S74 skip 102.4 0.448 Comparative J BC + 5% SLS skip
128.2 0.598 Comparative K BC + 10% LAS 0.55 76.15 0.331 Comparative
L BC + 10% Sandopan DTC skip 98.05 0.434 Comparative M BC + 10%
Acusol 445N skip 79.3 0.348 Comparative N BC + 10% Acusol 441 skip
96.75 0.422 BC = Base composition Lubrodrive .RTM. RX is a
phosphate ester based lubricant composition commercially available
from Ecolab, Inc. in St. Paul, MN. Dowfax .RTM. 8390 is a C.sub.16
alkyl diphenylene oxide disulfonate available from Dow Chemical Co.
in Midland, MI. Avanel .RTM. S74 is an ethoxylated alcohol
sulfonate available from BASF. SLS = sodium lauryl sulfate;
Available from a variety of sources including Henkel Corp. Emery
Group Cospha under the tradename of STANDAPOL .RTM. WAQ-LC; CALFOAM
.RTM. SLS-EO from Pilot Chemical Co. in Santa Fe Springs, CA;
STEPANOL .RTM. WAC from Stepan Co. in Northfield, IL; SULFOCHEM
.RTM. SLS from Chemron Corp. in Paso Robles, CA; and RHODAPON .RTM.
LX-28/AF2 available from Rhodia in Cranbury, NJ. LAS = linear alkyl
benzene sulfonate; Available from a variety of sources. Sandopan
.RTM. DTC acid is an ether carboxylate available from Clariant
Corp. Acusol .RTM. 445 N is a partially neutralized polycarboxylic
acid available from Robin & Haas in Philadelphia, PA. Acusol
.RTM. 441 is a partially neutralized polycarboxylic acid available
from Robin & Haas
[0076] Example 1 exhibited the lowest degree of weight loss of any
of the compositions, including the industry standard,
Lubrodrive.RTM. RX.
5TABLE 5 Chemical Comparative Tradename Description O (wt-%)
Example 3 Example 4 Calcium chloride 1.0 1.0 1.0 Oleyl 7.5 7.5 7.5
diaminopropane Lauryl propyl 3.0 3.0 3.0 diamine Dimethyl lauryl
4.5 4.5 4.5 amine Acetic acid; 80% 8.04 8.04 8.04 Polyethylene 3.0
3.0 3.0 glycol coco amine Isotridecyl alcohol- 9.0 9.0 9.0 9 mole
ethoxylate Sodium hydroxide; 1.65 1.65 1.65 50% Poly dicarboxylated
-- 5.0 10.0 Tergent .RTM. ethoxylated CS-1 alcohol; protectant DI
water 62.31 57.31 52.31
[0077] The above compositions were tested according to test method
no. 1 described above. The results are found in table 6.
6TABLE 6 Failures (#/24) Grade Comparative Ex O Amine acetate 3
1.88 lubricant Example 3 Amine acetate 0 1.54 lubricant with 5%
protectant Example 4 Amine acetate 0 1.17 lubricant with 10%
protectant
[0078] The dicarboxylated ethoxylated alcohol protectant was tested
in combination with an alternative lubricant which was based on the
sodium salt of a fatty acid. The following table shows the formulas
employed.
7TABLE 7 Trade- Chemical Comparative Comparative Comparative name
Description P (Wt-%) Q R Propylene glycol 14.98 14.98 14.98 Na salt
of oleic 20.00 20.00 20.00 acid Potassium 8.48 8.48 8.48 hydroxide;
45% Poly dicarboxylated 0 5.0 10.0 Tergent .RTM. ethoxylated CS-1
alcohol; protectant DI water 56.54 51.54 46.54
[0079] The compositions were tested according to test method no. 1
described above. The results are shown in table 8.
8TABLE 8 Failures (#/24) Grade Comparative P Fatty acid lubricant 4
1.25 Comparative Q Fatty acid lubricant 3 1.35 with 5% protectant
Comparative R Fatty acid lubricant 2 1.63 with 105 protectant
[0080] While the fatty acid based lubricant composition exhibited
improvement using a protectant in contrast to the fatty acid
lubricant with no protectant, the results were not as good as with
other types of lubricants.
[0081] The above disclosure is intended to be illustrative and not
exhaustive. The description will suggest many variations and
alternatives to those of ordinary skill in the art. All of these
alternatives and variations are intended to be included within the
scope of the attached claims. Equivalents to these specific
examples should also be encompassed by the attached claims.
* * * * *