[Paint Inspection]MEK rubbing test method and its limitations

Among the test methods, the most popular and easy to use test method for determining the degree of curing of the coating film would be the MEK rub test.

The term of MEK Rub Test is used much however Solvent Rub Test is the accurate term for MEK Rub Test.

It is called 'MEK Rub Test' because MEK is a strong solvent and mainly used among solvents, since the solvent-MEK is mainly used to evaluate the degree of cure of inorganic Silicate Inorganic Zinc Rich Primer, it is usually called more as MEK rub test than Solvent Rub Test.

Pros and Cons of MEK Rub Test

Pros: Easy, Quick, Simple
Cons: Comparative Evaluation, Lack of Reproducibility

Specifications of Solvent Rub Test

• ASTM D5402 Standard Practice for Assessing the Solvent Resistance of Organic Coatings Using Solvent Rubs
• ASTM D4752 Standard Practice for Measuring MEK Resistance of Ethyl Silicate(Inorganic) Zinc-Rich Primers by Solvent Rub

ASTM D5402 is a standard for evaluating the solvent resistance of organic paints, and ASTM D4752 is a standard for measuring the degree of curing of inorganic zinc primers through the solvent (MEK).

Solvent Rub Test Method (MEK Rub Test Method)

1. Prepare a fully cured control panel and a test panel.
2. Moisten a cotton swab or white cloth with a solvent(MEK) and rub it back and forth at a constant pressure.
3. Test on both panels under identical conditions.
4. Determine the degree of cure by comparing the changed state of gloss, coating loss, etc.

Limitations of Solvent Rubbing Test

MEK rubbing testing has limitations due to its test methods.

In the case of ASTM D4752 listed above, the standard provides a reference table to determine the degree of cure, but when used to determine the degree of cure of a organic paint, a generally comparable standard is required. So the disadvantage here is that the degree of cure must be determined by comparison between the fully-controlled panel and test panel.

In addition, when doing MEK test, it is necessary to know the type of paint. This is because some resins have weak solvent resistance to MEK or some solvent, and so even after proper curing, the gloss, film loss, or softening of the coating may be as if uncured.

The aggressive of solvents

MEK, Acetone >>>>>>> Xylene, Toluene

Depending on the resin type and requirements, solvent selection is also required, but MEK is usually used a lot.

One of the limitations of the MEK test is that it is a test conducted by a human.

As a result, test results may vary due to differences in rubbing speed, force, lasting time and other human factors.

(The pressing force, speed, and rubbing distance can be specified in the above ASTM standards or test requirements.)

However, it is widely used as a very useful test method to easily and quickly determine the degree of curing in the field and the laboratory, and test equipment with minimal human factor has been developed and used for more accurate testing in the laboratory.

TGIC Hazards Used as Powder Coating Curing Agent

Harmful Substances in Our Lives that We Do Not Know Well: TGIC (triglycidyl isocyanurate)

Mutagen! Organ Damage!

There are many harmful substances that we use but we do not know well in our lives.

Among them, we will learn about Triglycidyl Isocyanurate (TGIC) which is mainly used as a hardener.
TGIC is a raw material that is widely used as a curing agent in powder coatings using polyester resins.
The hardener is combined with the resin, which plays a role in the performance of the paint as a film.

There are two types of hardeners used in polyester resin powder coatings, a TGIC-free type hardener and a TGIC type hardener.

Powder coatings of polyester resins are wildly used in

• For indoor, industrial machines, interiors, furniture, home appliances, office furniture, electrical appliances, etc.
• For outdoor use, mobile parts, achitectural material such as fasade and window frames, electric control box, outdoor air-conditioner unit, etc.

Acute toxicity(GHS pictogram)

So now on, let's take a closer look at the harmfulness of TGIC.

• TGIC can be absorbed by the body through the skin. In addition, it can be introduced through the mouth or breath, and dust containing TGIC is often introduced into the body through breathing.
• If swallowed or inholed TGIC, it could damage the lungs, kidneys and digestive system.
• The more contact with TGIC, the more sensitive the body is to TGIC.
• TGIC can cause serious eye damage.
• Animal testing has shown that TGIC can cause genetic modifications.
• Blisters, itching, and swelling were observed in workers who used powder coatings or hardeners containing TGIC, asthma and leukocytosis in exposed powder spray workers, and atopic symptoms in exposed skin.
• Human tests of cancer patients showed toxic symptoms such as decreased spinal cord activity (blood production), dizziness, vomiting, white blood cell reduction, and partial hair loss.

There is still a lack of long-term testing for the effects of TGIC on the human body. So in addition to the hazards mentioned above, there may be more serious effects.

Health Hazard(GHS pictogram)

So please be aware of the following points when handling TGIC.

Where powder coatings containing TGIC are used,

1. Paint booths with limited access should be used.
2. Vacuums / suction cleaners should be used for cleaning to minimize dust.
3. If you use a powder coating with TGIC, you will need to wear personal protective equipment such as gloves, dustproof clothing, safety glasses and a dust mask.
4. Personal protective equipment must be worn in all processes of handling powdercoatings that containing TGIC.

To deal with TGIC as a raw material,

1. Vacuums cleaners should be used to minimize dust generation.
2. The process of handling raw materials must be designed to be sealed and automated as possible to minimize human access.
3. Dust collectors / suction facilities are provided throughout the workplace so that dust can be removed immediately.

Wherever TGIC is handled, safety training for personnel, training to wear personal protective equipment and provision of personal protective equipment should be provided and done.

TGIC should be more careful as its toxicity persists even after commercialization with raw materials.

Products containing TGIC are prohibited for use in some parts of China as well as in Europe.

Many countries are aware of the toxicity of TGIC, and regulations on safety training and dust collection facilities for workers are being implemented. Companies that used products containing TGIC are increasingly demanding TGIC-free products.

Reference :

1. NICNAS https://www.nicnas.gov.au/chemical-information/factsheets/chemical-name/triglycidylisocyanurate-tgic
2. WHO Concise International Chemical Assessment Document 8 TRIGLYCIDYL ISOCYANURATE

Link of the post in Korean: 유전자 변형! 장기손상! 유해물질 : TGIC(트리글리시딜 이소시아누레이트)

Most used E-mail abbreviations by Koreans in business

I will introduce some abbreviations and its meanings that Korean people like to use in a business e-mail.

ASAP: 'As Soon As Possible', It's a world famous, loved and most-used abbreviation and Koreans also love it and write it down on every e-mail they send.

CP: 'Cellular Phone'

Ex: 'Example'

FYI: 'For Your Information', This expression is usually used by a higher rank person when he/she share some information for his/her members.

HP: 'Home Page', it's company's web site.

PS: 'Post Script'

How to remove yellow mushrooms that suddenly appeared in plant pots

In order to improve the atmosphere and air of the house, the trend is to put plant pots in the house and it is called 'green interior'.

Pots are not completely sanitized products such as soil, fertilizers, etc., so when you put them into the house, there are things that we do not know inside pots. And it leads to unexpected pests, weeds and mushrooms in plant pots.

Among them, let's take a look at 'yellow primrose/horn mushroom (plantpot dapperling, Leucocoprinus birnbaumii)' which is a common mushroom in the house.

The yellow color of the mushroom is very pretty and cute, but the mushroom's spores is poisonous, and can harm the plant.

Yellow mushroom, where are you from?

Mushrooms are usually spread in pots through two routes.
The first is when spores come in through soil or fertilizer.
Second, spores can reach through a shovel, clothes or in the air. So ​​it's a good idea to get rid of potted mushrooms quickly before spreading spores.

Damn, the yellow is even beautiful!

How to remove mushrooms in pots

Unfortunately, it is very difficult to completely remove the mushrooms from the plant pots once they started to grow. As we know, mushrooms grow through hyphae, so even if you remove them, they can grow again at any time if the growth condition is correct.

This is why it is important to use fully sterilized soil of the plant pot when you plant.

Anyway let's see how you can get rid of mushrooms in the plant pot.

1. Remove the mushroom that you can see

First, when the mushrooms grow up, the spores from pileus will travel to everywhere they can reach though the air. So you need to quickly remove the mushroom and soil near the mushroom before the mushrooms spread to other plant pots.
Observe the plnat pots every day and remove the mushrooms.

Remove the yellow mushroom like this(with soil)

2. Change the whole soil in the plant pot.

In fact, removing mushroom such as above method is temporary. To remove the mushrooms, it is good to replace the whole soil of the plant pot. And it is important to remove soil from the roots of plants. It is also good method to soak roots in clean water.

3. Using a Mold / Mushroom Remover

It is said that mushrooms and fungi are almost identical. So if you use a mushroom / fungal remover where the mushroom is grown, you can see the effect. But be careful, it can harm the plant so before try, must see the detail of the remover.

4. Changing the environment

This is one of the easiest, surest and hardest ways. You can eliminate the environment where mushrooms grow by change location of the plant, light and air flow. If you remove the warm and humid environment, the mushroom spores will not grow. Also sunlight can kill the mushrooms and spores.

A good combination of the above methods will effectively remove the mushrooms in the pot. But it is very difficult to get rid of all the spores already spread around the pots, and if there is anything coming from outside (fertilizer, air, water, etc.), there is always the possibility of mushrooms growing again.


One hope, though, is that most mushrooms that grow in plant pots do not harm plants. If you don't eat it, there's no harm to person.

But if you raise young children or animals at home, they can touch or eat it because of curiosity. So even though the mushrooms are harmless, it would be better remove them as soon as possible.

Review for LG CordZero A9 wireless stick vacuum

I bought LG CordZero A9(A950) wireless stick vacuum and I have used it for long.

And now I can say pros and cons of LG CordZero A9 against a wire vacuum and its own.

First, the pros of LG CordZero A9.

As you expect, it is very convenience to bring where you want to clean at. Because it is cordless. And it has two battery packs,  you use the vacuum quite long. This stick vacuum has 3 mode by suction power: normal mode, power mode and turbo mode.

With two battery packs, its normal mode working time can be 60 mins, its power mode working time can be 18 mins and its turbo mode working time can be 12 mins.

Washable Microfilter

I think its working time is long enough on normal mode. And the sweeping roller which is attached to its basic cleaning stick head helps a lot to clean up dust and dirt on the floor, even though its normal(?) suction power on the normal mode. The roller is spinning by the separated head motor during the stick is working.

If you buy LG CordZero A9, it includes self-standing charging dock that its competition does not provide but LG CordZero A9 does. And it can be used as wall-mounting mode and compact mode. I use self-standing mode and it is pretty reliable and the bottom of the stand is heavy enough to keep the balance.

Tools of LG Cordzero A9(A950 model)

And about filter parts and a dust separator. It has two filter parts. Under the top lid where the air outputs, there is a HEPA filter to catch the particle matters and the filter is replaceable. And below the HEPA filter, there is a micro filter and under the micro filter, there is a cyclone filter(cyclone type dust separator). And the micro filter and the cyclone filter can be washable with tap water. With water you remove small dust on the filter easily. And they recommend that after washing the micro filter, it is dried for at least 24 hours. But they give two micro filters.

Self-stand mode of LG CordZero A9

Now here’s Cons of LG CordZero A9.

First, weaker suction power than a wire vacuum. A wire vacuum I have is much stronger than the LG CordZero A9. The wire vacuum is bought about 4 years ago and it also has cyclone type dust separator. However the cleaning capability can be similar as the LG CordZero A9 has a brush roller I think.

They say hassle-free dust bin maintenance. I hardly agree with it because there are hassles. When you open the dust bin, the location of open button is not good to handle. every time I open the lid of the dust bin, I find where the button is and my hand gets dirty from the floating dust.

And the cyclone filter inside of the dust bin works well but long hair is wound up the filter like a reel and it seems to disrupt and reduce its function.

Actually although it is easy to clean with LG CordZero A9, it is not easy to clean its own dust bin.

Learn Real Korean Slang

Learn Real Korean Slang for 인싸, 아싸, 존맛탱, 뇌피셜, 현타

As English has lots of slang, Korean also has lots and as a language, the slang are appeared and disappeared.

So I introduce recent Korean slangs.

1. 인싸(inssa), 아싸(assa)

인싸(in-ssa) is short for 'insider'. The insider means a person who is fashionable, extrovert, friendly. Simply it isn't the person like an outsider.
아싸(a-ssa) is the abbreviation of an outsider. As English dictionary says an outsider is a person who does not belong to a particular group.

And you can see or hear 핵인싸(hack in-ssa). 핵인싸(hack in-ssa) is 핵(hack) + 인싸(in-ssa). 핵(hack) means nuclear. It intends to give a word behind very strong feeling. And the feeling can be positive and negative. It's like 'as fuck'.
So 핵인싸(hack in-ssa) means very great 인싸(in-ssa).

And other use of 핵(hack) is 핵노잼(hack no-jam). 노잼(no-jam) means 'no funny', so 핵노잼(hack no-jam) means 'no funny as fuck'.

2. 존맛탱(jonmastaeng, jon-mat-taeng) or JMT

존맛탱 is kind of a shortened words but I'm not sure where it is from. Anyway, it means 'this is really taste as fuck'.

3. 뇌피셜(noepisyeol)

뇌피셜(neo-pi-syeol) has the meaning of official fact by someone-self. What it means that someone says something that he/she thinks the something is true and logical, but the thought is only from his/her brain. 뇌(neo) from 뇌피셜(noepisyeol) is a brain and 피셜(pi-syeol) means 'official'.

4. 현타(hyeonta), 현자 타임(hyeonja time)

현타(hyeonta) is an abbreviation of 현자 타임(hyeonja time). 현자(Hyeonja) means a wise man(sage), so if someone says 'I have 현자 타임(hyeonja time) or 현타(hyeonta).', it means like I'm like a wise man for now. And this expression comes from kind of sexual activities such as masturbation and being after sexual intercourse. When right after having sex, people usually have feeling or mood of calm or relaxed. So with that mood people may make a good decision like a wise man who is always calm and relaxed.
So when you have the urge of buying something that you cannot afford, and then you realize your situation and give up buying. That moment of the realization is called 현자타임.

119 & 112 Emergency Telephone Numbers of South Korea

119 and 112 are South Korean emergency telephone numbers. Such as emergency numbers around the world, this numbers are intended for use in emergency circumstances only, and using it for any other purpose can be a crime.

119 is for any disaster situation such as injury, fire, flood, landslide and etc. And if you use Korean cell phone, when you make a call for 119, they can trace your location for the emergency purpose. And they will show up to rescue and solve the situation.

112 is for any crime situation such as theft, assault, verbal abuse, trespassing and etc. When you call 112, you need to tell them where you are or where the crime happens at for fast response. The police will come as soon as possible if you call 112 anyway.

And here's a tip for Korean life. Actually 119 and 112 are almost the same. The emergency calling systems are integrated, so 119 can be connected 112 and 112 can be connected 119. But I recommend you to call 119 because as I mentioned they can have your location information from your call.

Yongkkaseu(Pork cutlet) for lunch at Mapo, Seoul

One of the most serious problem of office workers is to decide what to have for lunch.

For people who are near Mapo subway station, I suggest Yongkkaseu(용까쓰) restaurant.

You can find the Yongkkaseu just in front of the Samsung Plaza.

Anyway Yongkkaseu means dragon(Yong) and kkaseu from Donkkaseu(pork cutlet).

You can see Samsung Plaza(삼성프라자)

It has been opened for about over one year here.

And I think this place is a little pricy for lunch but they provide reasonable quality of Japanese style Donkkaseu, therefore it's a good choice sometimes.

Let's look at the menu.

Yongkkaseu Menu & Price

As you can see the photo above, their menu consists single cutlet menu, Udon noodle set menu and Buckwheat(Momil) noodle set menu.

And there is 용까스(Yongkkaseu) menu which has pork and fish cutlets, so you can eat two kinds of a cutlet.

There are three sauces: Worcester sauce, mustard sauce and ponzu sauce. You can eat the kkaseu in three difference tastes with these sauces.

The redish meat is tenderloin kkaseu and the other is fish kkaseu. They are both crispy and a little bit oily. For fish cutlet, there is tartar sauce and it is really good with because it remove oily fish taste.

Location: 8 Dohwa-gil, Dohwa-dong, Mapo-gu, Seoul, South Korea

Korean Version of this post: [맛집]마포역맛집 직장인 점심은 용까스

[DIY]Daesung Celtic Gas Boiler Room Controller Replacement

[DIY]Daesung Celtic Gas Boiler Room Controller Replacement

Daesung Celtic Gas Boiler is one of the products of the Korean boiler manufactures.

Its temperature controller(room controller) has two kind: Ondol type and Air temperature type.

What is Ondol?
Ondol is traditional Korean heating method that heat the floor and then the heated floor will increase air temperature also like a convection type heater. Actually Korean style boiler is basically following this method. But to control the temperature, there are two ways as the room controller is.

So, about room controller of Daesung Celtic Boiler. Ondol type room controller controls water temperature outputting from boiler. And Air temperature type room controller is checking room air temperature to maintain the air temperature.

And for me, it is not easy to use Ondol type room controller because I have not used and also it is kind of old. So I decided to replace the old one to the new one which has Air temperature controlling function.

My old room controller was 'DSR-110'. And I looked for compatible models to replace by asking its customer center.

Here's the list of the models below.

DSR-100 (not available)

DSR-120(not available), DSR-120B (not available, Back-light)

DSR-130 (not available)

DR-100 (Available, about 50,000 Won)

Not-available models are selling on second-handed shop.

BUT according to the sales policy of Daesung Celtic, it is not possible to sell 'new' room controller on the internet. So I had to go to the official dealer to buy the room controller(DR-100).

The picture below is the old one. It was very uncomfortable for me.

I bought the DR-100. Very simple.

To replace the old one, push it up to separate from the bracket that attached on the wall.

Then you can see two electric wires.

And just cut the wires carefully, be careful not to close the wires.

There are not + and -, it uses AC. Connect the wires to the controller like the picture below.

After the connecting job, check it out if it works right. Then join with the bracket.

This model:DR-100 supports two mode(Ondol and air-temperature). And you can change the mode simply by following the video below.

Link for Korean Version of the Post: [DIY]대성쎌틱 보일러 온도조절기(룸컨트롤러) 교체하기