U.S. patent application number 17/298161 was filed with the patent office on 2022-06-23 for method for treating an abrasive article, and abrasive article.
The applicant listed for this patent is Robert Bosch GmbH. Invention is credited to Johannes Huber.
Application Number | 20220193865 17/298161 |
Document ID | / |
Family ID | 1000006253523 |
Filed Date | 2022-06-23 |
United States Patent
Application |
20220193865 |
Kind Code |
A1 |
Huber; Johannes |
June 23, 2022 |
Method for Treating an Abrasive Article, and Abrasive Article
Abstract
A method for treating an abrasive article includes applying a
release agent dispersion onto at least one surface, which is
provided for abrading, of the abrasive article in order to produce
a cover layer. The release agent dispersion includes at least one
anti-adhesion agent. The release agent dispersion further includes
at least one film-forming agent.
Inventors: |
Huber; Johannes; (Konstanz,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Robert Bosch GmbH |
Stuttgart |
|
DE |
|
|
Family ID: |
1000006253523 |
Appl. No.: |
17/298161 |
Filed: |
November 18, 2019 |
PCT Filed: |
November 18, 2019 |
PCT NO: |
PCT/EP2019/081588 |
371 Date: |
March 10, 2022 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B24D 3/34 20130101 |
International
Class: |
B24D 3/34 20060101
B24D003/34 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 30, 2018 |
DE |
10 2018 220 672.4 |
Claims
1. A method for treating an abrasive article, comprising: applying
a release agent dispersion at least to a surface of the abrasive
article in order to produce a covering layer, wherein the surface
is configured for grinding, wherein the release agent dispersion
comprises at least one anti-adhesion agent, and wherein the release
agent dispersion further comprises at least one film-forming
agent.
2. The method as claimed in claim 1, wherein the release agent
dispersion further comprises at least one surfactant.
3. The method as claimed in claim 1, wherein applying the release
agent dispersion comprises: applying the release agent dispersion
to the surface of the abrasive article at a temperature of the
abrasive article in a range from 0.degree. C. to 100.degree. C.
4. The method as claimed in claim 1, wherein the release agent
dispersion has a solids content in a range from 20% to 60%.
5. The method as claimed in claim 1, wherein applying the release
agent dispersion comprises: applying the release agent dispersion
to the surface of the abrasive article using pulsed spraying.
6. The method as claimed in claim 1, wherein applying the release
agent dispersion comprises: applying the release agent dispersion
to the surface of the abrasive article during a production process
for the abrasive article, after a process step for heating the
abrasive article, and before a process step for cooling the
abrasive article.
7. The method as claimed in claim 1, further comprising: drying the
covering layer using an air stream in a process step for cooling
the abrasive article.
8. An abrasive article, comprising: a surface configured for
grinding, a covering layer configured to cover the surface, the
covering layer formed by applying a release agent dispersion to the
surface, the release agent dispersion comprising (i) at least one
anti-adhesion agent, and (ii) at least one film-forming agent.
9. The abrasive article as claimed in claim 8, wherein the
film-forming agent is a filming agent and/or a gap filler.
10. The abrasive article as claimed in claim 1, wherein the
film-forming agent is a filming agent and/or a gap filler.
Description
[0001] The invention relates to a method for treating an abrasive
article, where a release agent dispersion is applied at least to a
surface of the abrasive article intended for grinding to produce a
covering layer, where the release agent dispersion comprises at
least one anti-adhesion agent. Furthermore, the invention relates
to a corresponding abrasive article.
PRIOR ART
[0002] Methods for treating an abrasive article are already known,
for example from U.S. Pat. Nos. 5,766,277 B and 2,768,886 B, and in
these a release agent dispersion is applied at least to the surface
of the abrasive article intended for grinding to produce a covering
layer, where the release agent dispersion comprises at least one
anti-adhesion agent.
DISCLOSURE OF THE INVENTION
[0003] The invention proceeds from a method for treating an
abrasive article, in particular a coated abrasive article, where a
release agent dispersion is applied at least to a surface of the
abrasive article intended for grinding to produce a covering layer,
where the release agent dispersion comprises at least one
anti-adhesion agent.
[0004] An "abrasive article" is employed for the grinding or
abrasive working of a workpiece, in which the material of the
workpiece is mechanically removed in the form of swarf from the
surface of the workpiece. The abrasive article is, in particular, a
coated abrasive article. The abrasive article comprises an abrasive
article substrate, in particular a flexible abrasive article
substrate, having at least one layer. The abrasive article
substrate can comprise, in particular, paper, paperboard,
vulcanized fiber, foam, a polymer, a textile structure, in
particular a woven fabric, formed-loop knitted fabric, drawn-loop
knitted fabric, braid, nonwoven, or a combination of these
materials, in particular paper and woven fabric, in one or more
layers. The abrasive article substrate, in particular flexible
abrasive article substrate, gives the abrasive article specific
properties in respect of adhesion, elongation, tear strength and
tensile strength, flexibility and stability. In a coated abrasive
article, abrasive grains are fixed by means of a binder (often
referred to as base binder) on the abrasive article substrate. By
means of the binder, the abrasive grains are at least prefixed, in
particular fixed, in particular in a desired orientation and/or
distribution, on the abrasive article substrate. A person skilled
in the art will know of suitable binders for fixing abrasive grains
on the abrasive article substrate from the prior art. Such binders
of the prior art are typically solvent-based adhesives such as
polychloroprene. In addition to the binder as base binder, it is
possible to use a further binder known as a covering binder which
is applied, in particular, as a layer over the abrasive grains
which have been fixed by means of the base binder on the abrasive
article substrate. Here, the covering binder bonds the abrasive
grains firmly to one another and firmly to the abrasive article
substrate. Suitable covering binders, in particular, will be
adequately known to a person skilled in the art from the prior art.
Possible covering binders are, in particular, synthetic resins such
as for example phenolic resin, epoxy resin, urea resin, melamine
resin, polyester resin. In addition, further additives ("grinding
additives") can be provided in order to give the abrasive article
specific properties. A person skilled in the art will be familiar
with such additives.
[0005] Furthermore, alternative abrasive articles, such as for
example bonded abrasive articles, are in principle also
conceivable. Bonded abrasive articles are, in particular, typically
synthetic resin-bonded parting and grinding disks, with which a
person skilled in the art will be familiar. For synthetic
resin-bonded parting and grinding disks, a composition is produced
by mixing abrasive minerals together with fillers, pulverulent
resin and liquid resin and this is then pressed to give parting and
grinding disks of various thickness and diameters. In particular,
the parting and grinding disks also comprise woven fabric layers
composed of glass fibers. Curing of the composition typically
occurs at about 180.degree. C. In combination with the method of
the invention, advantages according to the invention can also be
achieved in the case of such abrasive articles.
[0006] The abrasive article has a surface intended for grinding,
i.e. an abrasive surface, in particular on that side of the
abrasive article on which the abrasive grains are fixed and
optionally provided with a covering binder and/or a further
additive. The abrasive surface of the abrasive article is moved
over a workpiece to be worked during a grinding operation, so that
a grinding effect is produced by the abrasive grains arranged on
the abrasive surface. The abrasive article can in principle be
present in various manufactured forms, for example as grinding disk
or as grinding belt, as sheet, roller, strip or as abrasive article
stock strip (e.g. in production).
[0007] The term "release agent dispersion" which is applied to the
surface intended for grinding of the abrasive article refers to, in
particular, a lubricant dispersion. The release agent dispersion is
employed for application of materials present in the dispersion to
the surface of the abrasive article, with these materials being
present as fine, essentially insoluble particles in the dispersion
medium (also: dispersion agent) of the release agent dispersion. In
one embodiment, the release agent dispersion comprises water as
dispersion medium. In an alternative embodiment, the dispersion
medium can also be formed by ethanol, alcohol, an organic solvent
or the like. The release agent dispersion is intended to be applied
to the surface of the abrasive article and bring about formation of
a covering layer on the surface.
[0008] The release agent dispersion comprises at least one
anti-adhesion agent, in particular as material present in the
dispersion medium. Here, an "anti-adhesion agent" is an agent which
prevents or reduces accumulation of swarf formed during a grinding
operation. The anti-adhesion agent serves to prevent or reduce
accumulation of swarf in the intermediate spaces between adjacent
abrasion grains, which can lead, in particular, to blocking or
clogging of the abrasive surface of the abrasive article. In
particular, the anti-adhesion agent serves to prevent or reduce the
effect in which swarf sinters together, sticks together or melts
together under the action of the heat arising in a grinding process
and melts on the abrasive surface of the abrasive article and in
this way likewise leads to blocking or clogging of the abrasive
surface of the abrasive article (as is often the case for, for
example, polymers, polymer surface coatings or the like to be
abrasively treated). In this way, a cutting capability and in
particular an operating life (service life) of the abrasive article
is advantageously improved. In this way, the anti-adhesion agent
serves as a type of lubricant between abrasive article and
workpiece surface to be worked during a grinding operation. In
particular, such an anti-adhesion agent is often referred to as
"stearate" in the literature about abrasive articles, even though
it can comprise any materials which are useful for preventing the
accumulation of swarf. For example, the anti-adhesion agent can
comprise metal salts of fatty acids (for example zinc stearate or
calcium stearate), salts of phosphate esters (for example potassium
behenyl phosphate), phosphate esters, urea-formaldehyde resins,
waxes, mineral oils, crosslinked silanes, crosslinked silicones,
fluorinated chemicals and/or combinations thereof as constituent.
Such anti-adhesion agents are often produced from fats in which a
mixture of fatty acids is present. For example, an anti-adhesion
agent--which is referred to as "stearate" in the literature--can
also contain calcium salts of other fatty acids, for example
palmitate, myristate or laurate. It is pointed out that such
anti-adhesion agents are known to a person skilled in the art, for
example from U.S. Pat. No. 5,766,277 B. The anti-adhesion agent
typically does not dissolve in the dispersion medium of the release
agent dispersion (for example water), so that a release agent
dispersion containing the anti-adhesion agent is present. In this
case, anti-adhesion agent particles, in particular very fine
anti-adhesion agents particles, "float" in the dispersion medium of
the release agent dispersion. In this sense, the anti-adhesion
agent or the anti-adhesion agent particles is/are present as fine,
essentially insoluble particles in the dispersion medium of the
release agent dispersion.
[0009] According to the invention, the release agent dispersion
comprises at least one film-forming agent, in particular a filming
agent and/or a gap filling agent. According to the invention, the
film-forming agent can be utilized to treat an abrasive article in
such a way that no strips or streaks remain on its surface as
residue of a coating with the anti-adhesion agent.
[0010] A "film-forming agent" refers to a substance which is
suitable and is in particular also provided for producing bonding
of individual anti-adhesion agent particles to the surface of the
abrasive article and/or to close gaps between individual
anti-adhesion agent particles on the surface of the abrasive
article. This makes it possible to produce a layer, in particular
uniform layer, or a film, in particular uniform film--the covering
layer according to the invention--from the many individual
anti-adhesion agent particles applied to the surface of the
abrasive article. The covering layer advantageously no longer has
individual anti-adhesion agent particles capable of refraction of
light. In other words, no light-refracting residues which
lead--depending on the position on the surface of the abrasive
article--to a nonuniform or inhomogeneous appearance (such as for
example streaks or strips on the surface) remain on the surface of
the abrasive article after carrying out the method of the
invention. Thus, a uniform covering layer which appears optically
transparent (or in some cases also translucent) through to
optically slightly opaque is produced on the surface of the
abrasive article. In particular, a covering layer having--depending
on the position on the surface of the abrasive article--a uniform
or homogeneous refractive index is made possible.
[0011] On the basis of present-day knowledge, the production of a
uniform film which appears optically transparent through to
optically slightly opaque appears to be possible by means of
partial dissolution and joining of neighboring anti-adhesion agent
particles and/or by filling-up of gaps between neighboring
anti-adhesion agent particles. A film-forming agent which brings
about partial dissolution and joining of (two or more) neighboring
anti-adhesion agent particles will in the context of the present
text be referred to as "filming agent". In particular, the filming
agent brings about adhesive bonding and filming (i.e. film
formation) of adjacent anti-adhesion agent particles. In
particular, this partial dissolution, joining, adhesive bonding
(may also be characterized as melting) and/or filming of adjacent
anti-adhesion agent particles is made possible at advantageously
low temperatures in the range from 0.degree. C. to 100.degree. C.,
in particular from 15.degree. C. to 80.degree. C., very
particularly from 30.degree. C. to 60.degree. C. The filming agent
thus acts in a manner analogous to an adhesive which partially
dissolves the materials of objects to be joined in the surface
region and subsequently dries. As a distinction from a filming
agent, a film-forming agent which brings about the filling of gaps
between neighboring anti-adhesion agent particles will be referred
to as "gap filler". A gap filler advantageously has a refractive
index similar to that of the anti-adhesion agent particles, so that
no or only very little refraction of light occurs at the places
filled with gap filler between adjacent anti-adhesion agent
particles and the gap filler thus likewise serves to produce an
optically transparent (or sometimes also translucent) but
homogeneous covering layer.
[0012] In one embodiment of the method, the film-forming agent
comprises at least one constituent which is suitable for partially
dissolving anti-adhesion agent particles. The constituent can, for
example, be selected from a list, where the list comprises at least
organic acids, alcohols, amines, phosphanes, lactic acid, acetic
acid, salts of lactic acid, salts of acetic acid, in particular
ammonium salts of lactic acid (ammonium lactate) or ammonium salts
of acetic acid (ammonium acetate), polyethylenimine, polyethylene
glycol, urea and mixtures thereof. Polyethylenimine in particular
has good properties as film-forming agent, in particular as filming
agent, since it becomes solid and does not diffuse after treatment
of the abrasive article, in particular does not diffuse into the
abrasive article. Polyethylene glycol has been found to be an
advantageous gap filler. Urea, which is partially dissolved by one
of the abovementioned film-forming agents, is likewise suitable as
good gap filler.
[0013] In an embodiment of the method, the release agent dispersion
contains at least one surfactant. Surfactants which are able to
achieve good leveling, i.e. good spread, of the release agent
dispersion on the surface of the abrasive article while the
abrasive article is being treated in the method of the invention
are particularly suitable. A surfactant leads to an advantageous
equalization of amounts of release agent dispersion applied to the
surface if the release agent dispersion is not applied
homogeneously over the surface (self-leveling). This equalization
occurs by flow of the release agent dispersion.
[0014] In an embodiment of the method, the release agent dispersion
is applied to the surface of the abrasive article at a temperature
of the abrasive article in the range from 0.degree. C. to
100.degree. C., in particular from 15.degree. C. to 80.degree. C.,
very particularly from 30.degree. C. to 60.degree. C. In
particular, a temperature of above 0.degree. C. leads to
evaporation of the dispersion medium water, with the anti-adhesion
agent and the film-forming agent remaining on the surface of the
abrasive article--where a gap filler fills gaps between
anti-adhesion agent particles and/or a filming agent partially
dissolves and joins adjacent anti-adhesion agent particles--and the
optically homogeneous covering layer being formed in this way. The
higher the temperature selected, the more quickly does evaporation
of the dispersion medium occur. On the other hand, heating of the
abrasive article to a high temperature is costly and complicated in
terms of manufacturing technology. In one embodiment of the method,
the release agent dispersion is applied to the surface of the
abrasive article during the production process of the abrasive
article, in particular after a process step of heating the abrasive
article, very particularly before a process step for cooling the
abrasive article. Accordingly, it is sufficient in order to
maintain the proposed temperatures to treat the abrasive article in
the still-hot state during or immediately after manufacture
thereof--during which heating to typically above 70-140.degree. C.
is carried out in order to cure the binder. Here, heating means
heating of the abrasive article to significantly above room
temperature, i.e. above 30.degree. C., in particular above
50.degree. C., very particularly above 70.degree. C. According to
the invention, residual heat still present in the abrasive article
can be utilized and it is not necessary to reheat the abrasive
article in a heating oven in a (further) process step of
after-treatment. Here, "production process" means the sequence of
process steps which serve to manufacture and provide the abrasive
article. In an embodiment, these process steps can be formed by (1)
application of base binder to an abrasive article substrate, (2)
sprinkling of abrasive grains onto the abrasive article substrate
covered with base binder, (3) curing of the base binder, (4)
application of a covering binder, (5) drying and/or curing of the
resulting abrasive article by heating of the abrasive article, (6)
cooling of the abrasive article and (7) finishing (stamping or
laser cutting) of the abrasive article. According to the invention,
the release agent dispersion can be applied to the surface of the
abrasive article during the production process of the abrasive
article, in particular after the process step (5) of heating to
effect drying and/or curing of the abrasive article (also: drying
process step), very particularly before the cooling process step
(6) for the dried/cured abrasive article and the residual heat
present in the abrasive article can be utilized in this way.
Furthermore, the method of the invention can be integrated in this
way into an existing process chain of the production process and a
corresponding process facility, for example into an existing
manufacturing plant, without further, in particular complicated,
machines or restructuring being necessary in the process chain
and/or process facility. In particular, no separate heating oven is
therefore required and/or no double utilization of an existing
heating oven for drying/curing (in process step (5)) and for later
reheating in order to treat the abrasive article is necessary for
carrying out the method. In one embodiment, the release agent
dispersion can be applied directly "in-line" onto an abrasive
article stock strip (referred as stock strip) moving through a
manufacturing plant and which has previously been heated for drying
and curing of the binder, with the dispersion medium water of the
release agent dispersion evaporating and filming of the surface
occurring to form the covering layer.
[0015] Furthermore, the covering layer produced by application of
the release agent dispersion to the surface of the abrasive article
can be dried in the process step for cooling the abrasive article
by means of an air stream in such an embodiment of the method.
Here, the cooling effect exerted on the abrasive article is
reinforced and drying of the covering layer is at the same time
accelerated.
[0016] The release agent dispersion can be applied to the surface
of the abrasive article by means of doctor blade coating,
rolling-on, printing, brushing or the like. In one embodiment of
the method, the release agent dispersion is applied to the surface
of the abrasive article by means of pulsed spraying. Pulsed
spraying--i.e. repeated spraying with brief interruptions
(intermittent spraying)--assists metering because the pressure and,
associated therewith, droplet formation of the release agent
dispersion applied to the surface of the abrasive article remain
constant. Furthermore, the amount of release agent dispersion
sprayed on can be altered in a simple way by varying the opening
time of the spray valve (for example by changing the opening time
from 10 milliseconds to 50 milliseconds per impulse). In
particular, an otherwise necessary cleaning of adhesive boat and
application roller(s) can be avoided in the cleaner process
operation of spraying compared to a rolling of a solution onto the
surface of the abrasive article as is known from the prior art.
[0017] In an embodiment of the method, the release agent dispersion
has a solids content in the range from 20% to 60%, in particular
from 25% to 50%, very particularly from 30% to 40%. The values
according to the invention are advantageous solids contents for
processing the release agent dispersion. A particularly high solids
content makes it possible to achieve a high density of
anti-adhesion agent particles sprayed on the surface of the
abrasive article. On the other hand, a low solids content (i.e. a
low-viscosity or fluid property) allows particularly good
meterability and processability by means of the spray valves (spray
nozzles), because these do not block. Furthermore, a release agent
dispersion having a low solids content which has been sprayed onto
the surface can distribute more readily on or over the surface (by
flowing). In one embodiment, the solids content can be 33%.
[0018] The invention also provides an abrasive article which has
been treated by a method according to the invention.
DRAWINGS
[0019] The invention is explained in more detail in the following
description on the basis of embodiments depicted in the drawings.
The drawings, the description and the claims contain numerous
features in combination. A person skilled in the art will also
advantageously look at the features individually and assemble them
to give useful further combinations. Identical reference numerals
in the figures denote identical elements.
[0020] The figures show:
[0021] FIG. 1 a part of an illustrative embodiment of an abrasive
article according to the invention with abrasive grains in a
schematic sectional view;
[0022] FIG. 2 a process flow diagram for depicting the method of
the invention for treating an abrasive article;
[0023] FIG. 3 a process flow diagram for depicting an illustrative
integration of the method of the invention as per FIG. 2 into a
manufacturing process for an abrasive article.
[0024] FIG. 1 shows a part of an illustrative embodiment of an
abrasive article 10 according to the invention with abrasive grains
12 in a schematic sectional view. In the embodiment depicted, the
abrasive article 10 is a coated abrasive article 10 having an
abrasive article substrate made of vulcanized fiber. The abrasive
article substrate 22 made of vulcanized fiber serves as flexible
substrate for the abrasive grains 12. Vulcanized fiber is a
composite material composed of cellulose, in particular cotton or
cellulose fibers, and is adequately known to a person skilled in
the art as flexible substrate for abrasive articles from the prior
art. The abrasive grains 12 are fastened by means of a binder 20,
in particular a base binder 24, in the form of, for example,
phenolic resin, to the abrasive article substrate 22. The layer of
base binder 24 and abrasive grains 12 is additionally coated with a
covering binder 26 (the covering binder 26 likewise represents a
binder 20), in particular likewise composed of phenolic resin.
[0025] The abrasive article 10 has been treated by the method
according to the invention for treating an abrasive article 10, by
a further covering layer 30 being applied to the surface 28
intended for grinding of the abrasive article 10. The application
of the covering layer 30 is carried out by use of the method 100
according to the invention, cf. FIG. 2.
[0026] FIG. 2 shows a process flow diagram to depict an embodiment
of the method 100 according to the invention for treating an
abrasive article 10, with a release agent dispersion for producing
a covering layer 30 being applied to at least one surface 28 of the
abrasive article 10 in the treatment of the abrasive article
10.
[0027] In a first method step 102, a release agent dispersion
comprising at least one anti-adhesion agent is provided. In this
embodiment, the release agent dispersion further comprises a
surfactant. This release agent dispersion here comprises, for
example, water as dispersion medium, a stearate, in particular a
calcium stearate, as anti-adhesion agent. The release agent
dispersion here has a solids content in the range from 30% to 40%,
for example 35%.
[0028] In method step 104, the release agent dispersion provided is
admixed with at least one film-forming agent. Admixing is carried
out, in particular, by blending or stirring the mixture of release
agent dispersion and film-forming agent. The film-forming agent
comprises, in particular, a filming agent and/or a gap filler. In
an embodiment, the film-forming agent is a mixture of lactic acid
and polyethylene glycol. In method step 106, the release agent
dispersion which has been admixed with the film-forming agent is
applied to the at least one surface 28 of the abrasive article 10.
Application is carried out in this embodiment by pulsed spraying
onto the surface 28 of the abrasive article 10 using at least one
atomizer nozzle (not shown in more detail here). The pulsed
spraying is carried out here by repeated intermittent spraying at
an average frequency of 20 Hz, with valve opening times of about 20
milliseconds.
[0029] FIG. 3 shows a process flow diagram to depict an exemplary
integration of the method 100 according to the invention as per
FIG. 2 into a manufacturing process 200 for an abrasive article 10.
The manufacturing process 200 comprises at least the following
process steps.
[0030] In process step 202, an abrasive article substrate 22, for
example composed of vulcanized fiber, is provided. In process step
204, a base binder 24 is applied to the abrasive article substrate
22, for example by doctor blade coating or rolling-on. In process
step 206, abrasive grains are sprinkled, for example by means of
electrostatic sprinkling as is known from the prior art, onto the
abrasive article substrate 22 which has been covered with base
binder. In process step 208, the base binder 24 is firstly cured
and subsequently coated in process step 210 with a covering binder
26, in particular by rolling-on or brushing-on. In process step
212, the abrasive article 10 obtained in this way is dried/cured
(in particular the covering binder 26 is also cured) by conveying
it through a heating oven and thus heating it. The heating oven is,
for example, heated to 120.degree. C. In parallel to these process
steps 202 to 212, the method steps of the method 100 according to
the invention can be carried out, in particular carrying out the
method steps 102 to 104, as depicted in FIG. 3 (as an alternative,
these method steps 102 to 104 can also be carried out before or
after the process steps 202 to 212 are carried out). After heating
and drying/curing the abrasive article 10 in process step 212, the
release agent dispersion is applied to the surface 28 intended for
grinding of the abrasive article 10 in process step 214, i.e.
method step 106 of the process of FIG. 2 is carried out. At this
point in time, the release agent dispersion comprises at least one
anti-adhesion agent and a film-forming agent, optionally a
surfactant. At the point in time of application of the release
agent dispersion, the abrasive article 10 has a temperature of
about 50.degree. C. As described, application is carried out by
means of pulsed spraying (cf. above in respect of method step 106).
The covering layer 30 produced by application of the release agent
dispersion to the surface 28 of the abrasive article 10 is dried by
means of an air stream in a process step 216 for cooling (cooling
process step) the still hot abrasive article 10, with the still hot
abrasive article 10 being cooled at the same time and the
dispersion medium water of the release agent dispersion applied to
the surface evaporating at the same time. As a result of the
residual heat, the film-forming agents, i.e. the gap filler and the
filming agent, react and form an optically homogeneous, i.e.
streak-free, covering layer. Finally, the abrasive article 10
obtained in this way can be finished, for example by stamping or
laser cutting, in process step 218.
* * * * *