How do air-activated heat packs and eye masks work?

October 28, 2016

Air-activated heated eye masks like the Kao Megurhythm Steam Hot Eye Mask are awesomely convenient little inventions. They heat up instantly once you open the package, so you don’t have to mess around with hot water or microwaves. Here’s the science behind how they work!

Air-activated eye masks work the same way as the air-activated heat packs called kairo that are incredibly popular in Japan, especially in winter. These heat packs work thanks to a heat-releasing (exothermic) chemical reaction that starts when you expose the porous pack to oxygen in the air.

Here’s the reaction:

4Fe_(s) + 3O_2(g) + 6H₂O_(l) → 4Fe(OH)_3(s) ΔH < 0

iron + oxygen + water → iron(III) hydroxide + heat

This oxidation process is pretty much the same as what happens when iron rusts. The product itself contains iron powder and water but no oxygen, so the reaction can’t proceed until the sealed bag is open and oxygen from the air can work its way through the holes in the pack to reach the other reactants. The bags also often contain salt which acts as a catalyst to speed up the reaction, and vermiculite and activated carbon which can help distribute water and oxygen more evenly for a more sustained reaction, as well as insulate the reaction and trap the heat in the heat pack. The inside of a heat pack I bought from Daiso looks like this after 6 hours, with a pad of black activated carbon and brown iron(III) hydroxide:

Remington PROluxe Salon Dryer and Straightener Review

September 23, 2016

Remington have released two styling products that promise to give salon quality results at budget-friendly prices: the PROluxe Salon Straightener and Dryer. I was lucky enough to try both of them.

Both PROluxe products have what Remington call “PROheat technology”, which improves even heat distribution for more effective and less damaging styling. In straighteners, the heat of the plates drop as you glide it along cold hair, so even if the temperature is set right, you’ll still have to go over your hair a few times, causing possible uneven heating and spots with increased damage. The PROLuxe straightener uses a digital sensor to monitor the heat and immediately boost it back up when it drops for “one pass” straightening. The ceramic coating has 15 times more ceramic than a regular straightener as well to promote even heating, and is extra smooth to limit snagging. There’s also a handy switch to lock the plates closed for easier storage.

I had a wave put in my hair at Edwards and Co salon using the PROLuxe straightener – I was impressed by how quick it was, and how long it lasted (3 days with a metric truckload of dry shampoo, including 2 dance classes!). If only the straightener came with a stylist who actually knows what they’re doing and can see the back…

How Does the Clarisonic Cleansing Brush (Theoretically) Work?

September 3, 2016September 2, 2016

How Does the Clarisonic Brush (Theoretically) Work?

I always assumed that the Clarisonic cleansing brush was an attempt to clean the skin via sonic cavitation, which is when sound waves cause tiny jets of water to smash into a surface to clean it, like a thousand tiny power hoses (that’s how sonic jewellery/glasses cleaners work). But for sonic cleaning via cavitation to work, you need a hard surface, which glasses and jewellery are, but skin is not, so I was pretty confused.

I recently stumbled upon a paper from 2006 in the Journal of Cosmetic Dermatology, where the inventors of the Clarisonic discuss how it’s designed to work. (Important note: the paper doesn’t present any data of the Clarisonic in action to show that that’s how it actually works, but it’s interesting to see the theoretical background anyway!)

The Clarisonic Brush Head

The Clarisonic brush head has two parts: an outer ring that’s fixed and doesn’t move, and an inner section that’s attached to a motor inside the handle.

From the Clarisonic patents, the inner section rotates back and forth between 8 and 26°, at a frequency of 176 Hz (i.e. it makes 176 cycles from the left to the right and back again in a second; you can also think of it as 352 “sweeps”).

How the Clarisonic Brush Head Works

Here’s the question: if you put the brush against your skin, which part of your skin gets cleaned the most? If you’re a normal sensible person who hasn’t looked at the Clarisonic website in much detail, you’d say, “the part of your skin that’s sitting under the moving inner portion.”

This is where it gets really interesting – the part of the skin that the brush is designed to deeply clean is actually the part with no bristles on it! It’s the skinny ring in between the outer and inner portions (0.05-0.125 inches, or 1.3-3.2 mm according to the patents).

Daiso Silicone Sheet Mask Review

July 8, 2016

My skin gets dehydrated in winter despite my best efforts to gently cleanse and exfoliate it, so I’ve been using hydrating masks (both sheet and not) to try to boost the moisture levels. I came across this nifty silicone sheet mask tool at Daiso and knew I had to get one!

The Daiso Silicone Mask is essentially a silicone sheet mask with ear loops to hold it in place.

You can use it on top of a sheet mask, or on top of a regular mask or even by itself, according to the instructions on the back. I’ve also been using it over hydrating masks.

There’s a bunch of advantages to using this mask:

It keeps your face warm when masking in winter: When water evaporates, it takes a whole bunch of heat with it, which is why sweating cools you down so well and why hypothermia happens so much more easily when you’re wearing wet clothes. Some people use sheet mask warmers, but the mask only stays warm for a few minutes after application, and if it gets too hot, there’s the chance that sensitive ingredients could break down.

When water evaporates from the top of the sheet mask, it carries all the other ingredients with it. This means that as your mask evaporates, unless it stays absolutely soaked in essence, all the good ingredients will end up clustered on the side furthest away from your skin. The sheet mask slows down evaporation so the ingredients don’t migrate away.

My Lazy Hair Routine

June 30, 2016

My Lazy Haircare Routine - Luxcurly Hair Curler

My poor neglected hair. I’ve really tried to look after it, but unfortunately I have no willpower so I’ve been pretty slack. Luckily, I’ve found a few lazy ways to try to keep my hair OK with a minimum of effort!

Luxcurly Rotating Curling Iron

I’m still in love with the Luxcurly line of rotating curling irons for when I want curly hair but I also don’t want to burn my fingers or get DOMS from manipulating a wand around my head for an hour. The barrel spins with a touch of a button, so you can just clip your hair in, spin and it does the hard work for you! (You will still need to comb your hair and clip it and all that unfortunately – it’s not quite as good as a human hairdresser, but it’s pretty close!). Amazingly, it manages to make my stubbornly straight Asian hair hold a curl for hours, with the help of a ton of hairspray.

Nape Undercut

I’ve been using this Remington Barber’s Best Hair Clippers to give the boyfriend haircuts that are both cheap and don’t look weird. I think he got sick of me demanding a backrub for each haircut, so he convinced me to let him give me a nape undercut…just in time for winter. Oops! It’s a bit cold when I put my hair up, but it’s made my hair dry faster and feel lighter, plus it looks the same when I have my hair down or in a low ponytail.

PuraBeaute Sonic Facial Cleansing Brush Review

May 16, 2016May 16, 2016

About the PuraBeaute Sonic Facial Cleansing Brush

The PuraBeaute sonic facial cleansing brush is rechargable and completely waterproof, with a magnetic charger so all the electronics are confined in the plastic case. The brush head vibrates over 300 times a second, with your choice of 3 speeds, indicated by a green (sensitive), yellow (normal) or red (intense) light around the buttons. It has a built-in timer sequence which pulses to tell you to change where you’re washing – it gives you 20 seconds for your forehead, 20 seconds for your chin and 10 seconds per cheek.

The PuraBeaute comes with click-on Everyday (black ring) and Gentle (grey ring) brush heads. You can also buy the stiffer Deep Cleanse brush head for a more thorough clean, or the Soft Silk brush head for very sensitive skin.

The brush also comes with a stand and a USB charging cable which can be attached to a wall plug (provided) or a computer.

How Make-Up Remover Cloths Work and Review

April 26, 2016

What’s a make-up remover cloth?

Make-up remover cloths are usually a soft fleecy flannel with dense, fluffy fibres about half a centimetre long. To use a make-up remover cloth, you simply wet it with warm water and rub on your face in small circular motions – and your make-up comes off, without using any “chemicals” (well, except for dihydrogen monoxide (H₂O) and the substances in the cloth, the glucose you use to power your hands etc. etc.).

What sorcery is this? Here’s how this magic cloth works…

How do make-up remover cloths work?

The key difference between these make-up remover cloths and regular washcloths is surface area. The dense pile is made of many small threads, so there are a lot more threads in cloth than if they were normal sized.

Surface area is important for a few reasons:

1. Friction. To lift the make-up from the skin, the fibres need to grip onto the make-up and pull it off. The greater the surface area, the more grip and friction each wipe will have without you having to push down so hard – instead of 5 large fibres going over a particular area, you get 50 fibres. It’s like with shoes – a shoe with a perfectly flat sole is going to have worse grip than a shoe with a ribbed sole, which has a better surface area. This means the cloth will remove more make-up with less irritation.

2. More thorough cleaning. Smaller fibres can get into cracks too small for normal cloths, and can get under finer particles of make-up.

3. Adsorption. If there’s enough friction, the make-up will lift off the skin, but then it’ll just be smeared around unless the cloth can grab onto it. Luckily, at a molecular level, everything is quite sticky with adhesive forces (technical term: van der Waals forces). Because there are so many fibres, these cloths can bind to dirt and hold it better than a normal cloth.

Remington i-LIGHT Pro+ Face & Body IPL 5 month review

May 15, 2016April 9, 2016

Quite a few readers have asked me to update on how effective the Remington i-LIGHT Pro+ Face & Body IPL machine (model IPL6500AU) is, long(ish) term. So here’s a review of the results 5 months later! Check out my earlier posts for an overview of the Remington i-LIGHT IPL machine and how it to use it.

Overview of the Remington i-LIGHT Pro+ Face & Body IPL Machine

The i-LIGHT Pro+ is a compact unit, featuring:

An infinity bulb which (theoretically) never needs replacing
Face and body attachments for treating different areas
A skin sensor to check if your skin is suitable for IPL
5 energy settings, to ensure comfort

A full treatment regimen is 3 sets of treatments, 2 weeks apart – top up treatments may be necessary.

5 Month IPL Update

I originally did three areas (right armpit, right bikini line, left forearm). The area I wanted to reduce hair in most was my armpit. Unfortunately, I managed to get an ingrown hair in the armpit that I was treating, which then turned into a minor cyst (gross, I know – sorry!), so I couldn’t continue after the 3rd treatment, which was annoying because that’s where I was seeing the most improvement. I also stopped treating the other areas as well around this time (early November).