The "Very Best Record Cleaning Formulation"

I just came upon this thread so I figured I would provide my experience with ultrasonic cleaning of vinyl records.

I studied the effect of ultrasonic cleaning of vinyl records back in the late 70s when I built my first ultrasonic record cleaner. In my laboratory, we routinely used ultrasonic cleaners for many laboratory applications. Before I actually cleaned any records in an ultrasonic bath, I wanted to be sure that there were no detrimental effects. To evaluate the effectiveness of ultrasonic cleaning of records and to determine if there were any detrimental effects, I used several analytical techniques. My primary analytical techniques were Photoelectron Spectroscopy (HP 5950A Photoelectron Spectrometer) and optical microscopy (Olympus Laboratory Microscope at about 10,000X). Photoelectron Spectroscopy is sensitive to the top 5 nanometers of a sample surface and can determine the chemical structure of the record surface and the chemical composition of contaminants on the record surface. I also employed several supporting techniques for certain experiments including; Mass Spectrometry (MS), Liquid Chromatography (LC), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR).  These experiments were all done on sacrificial records that were cut into 1 cm squares. These 1 cm square samples were analyzed before and after various cleaning procedures. In some cases, the test samples were purposely contaminated with finger prints and various greases and oils to simulate a heavily soiled record.

The variables Investigated include:

Ultrasonic Bath Solution:

1 - Triply distilled water prepared in my laboratory

2- Deionized water  prepared in my laboratory

3 - The addition of either 2.5% or 5% concentration of an alcohol (either isopropyl or ethanol) to each of the above.

Surfactant - I experimented with several different nonionic surfactants which were in use in my laboratory. I settled on several alcohol ethoxylate surfactants with the general structure R(OCH2CH2)nOH where R is the alkyl chain and (OCH2CH2)n is the ethylene oxide (EO) chain. Their chemical structure varied with the length of the alkyl chain and/or the ethylene oxide chain. For reference, the alcohol ethoxylates I used are similar in structure to Dow’s Tergitol 15-S series of surfactants which are secondary alcohol ethoxylates.

Time in the ultrasonic bath - My experiments demonstrated that longer than a few minutes in the ultrasonic bath had little beneficial effect on the overall cleaning process and the possibility of a detrimental effect. Most of the cleaning took place in the first few minutes in the bath. I did observe that extended time in the bath would leach plasticizers, stabilizers or other additives from the bulk of the record test samples and eventually pit the record test sample surface. So I tried to keep the time in the bath to a minimum.

Summary of experimental results:

1. Both trtiply distilled water and deionized water in the ultrasonic bath worked surprisingly well at removing much of the contaminants on the test samples in many cases. Testing on UHV prepared Si wafers in the ultrasonic bath indicated that deionized water did leave some residue while triply distilled water left little to none that could be detected. The small amount of residue left by the deionized water is probably not a major concern.

2. The addition of the surfactant to the ultrasonic bath solution improved the overall contaminant removal efficiency compared to only water.

3. The addition of an alcohol to the ultrasonic bath solution had little effect on the contaminant removal efficiency except in a few select cases. For these few cases, ethanol was slightly better than isopropyl at contaminant removal.

4.  All the surfactants that I tried exhibited similar contaminant removal properties and did a reasonably good job of cleaning heavily soiled record test samples. The biggest difference between the surfactants was the amount of residue left behind after the ultrasonic bath. In general, the lower molecular weight surfactants were found to leave less residue on the record test sample surface and were removed more easily with a distilled water rinse after the ultrasonic bath.

5. I will mention that I did try Dawn detergent just to see how effective it was at cleaning records and whether it had any detrimental effects. Dawn was very good at cleaning the most heavily soiled record test samples but left considerable residue which required an extended rinsing to remove. I would only recommend Dawn detergent for heavily soiled records and not for regular use. Dawn does contain as many as 17 ingredients, some of which may cause issues with records after long term exposure.

6. When I finally set up my ultrasonic cleaner for my records, I only used distilled water and the appropriate amount of the alcohol ethoxylate surfactant in the bath. I typically had it set at about 2 RPM and a run time of about 6 to 9 mins. That corresponds to actual exposure times of ~ 2 to 3 minutes (~1/3 of the record surface is in the bath at a given time). For my setup, between 1 to 3 RPM worked fine. The 6 min time was for my records purchased new which had no obvious contamination and the 9 min time was for previously owned records that exhibited some surface contamination. For records with significant visible contamination, I would add some ethanol (2.5 to 5%) to the bath solution.

The spindle assembly on my DIY ultrasonic cleaner could hold up to 10 records and had a variable speed motor attached.  The assembly rode on a track with a lock nut so the spindle assembly could be raised and lowered into the bath. I actually employed 2 ultrasonic baths both fitted with a track to attach the spindle assembly. The second bath was only used with distilled water. Primarily I used this second  bath to spin rinse records that had been cleaned in the first ultrasonic bath. In some cases I did a followup ultrasonic cleaning with distilled water in the second bath for heavily soiled records. After a distilled water rinse in the second bath, I would raise the spindle assembly and spin dry the records at a faster rate. This left no visible water marks on the record surface and only some residual water droplets on the record outer edges which I removed with a clean room wipe.

I used this ultrasonic cleaner for over 30 years with excellent results and never any issues with my records. Even new records exhibited an improvement in SQ after ultrasonic cleaning. Typically once a record is ultrasonic cleaned, it will need no further ultrasonic cleaning if handled properly. The total time to mount, ultrasonic clean, rinse and spin dry 10 records was typically about 20 minutes. Heavily soiled records might take a few minutes longer.

@lewm Regarding isopropyl alcohol causing damage to vinyl records. My experiments using several surface sensitive analytical techniques have shown that neither isopropanol or ethanol will cause any damage to a vinyl record surface if used in dilute solutions for short exposures. My analysis of vinyl record test samples exposed to pure isopropanol or pure ethanol for extended periods does indicate that additives will begin to leach from the bulk of the vinyl record to the surface.

@rich121 I agree with your observations regarding ultrasonic cleaning of records. I always found that ultrasonic cleaning of new records resulted in an improvement in SQ, as you stated less pops/clicks and more noticeable detail.

@lewm I can’t put a specific number on dilute alcohol solutions but I would think that anything below 25% and exposed for a few minutes should not be a concern.

The migration of additives from the bulk to the surface is a common phenomenon in polymers which can be accelerated by contacting the surface of the polymer with a suitable solvent. Vinyl records are no different. The detection of additives migrating to the surface of a vinyl record is trivial using Photoelectron Spectroscopy as long as the additive has a suitable chemical signature for identification. For some additives this is not the case. In these cases I carried out two different experiments. One method was to dry the alcohol solution on a suitable substrate (typically a UHV prepared Si wafer) and analyze the residue with Photoelectron Spectroscopy and Thermal Desorption Mass Spectrometry. The second method was to just do Liquid Chromatography and Mass Spectrometry on the solution.

If I was doing the experiments today, I would include TOF Static SIMS and ATR-FTIR Spectroscopy along with Photoelectron Spectroscopy for analysis of vinyl record test samples.

lewm posted "Have you identified molecules that elute with IPA? In this regard, is ethanol safer? Thx."

@lewm The main additives diffusing to the surface with concentrated alcohols were identified as plasticizers as well as some stabilizers, scavengers and conditioners. Ethanol and Propanol behaved similarly in this regard although I did not study this in great detail with vinyl records so there may be subtle differences. I was not able to detect any leaching of additives with alcohol concentrations <10% for a few minutes exposure.

@mijostyn

Regarding your use of brake cleaning fluid on records. I have no idea what brake cleaning fluid you used, but I have only seen two types of brake cleaning fluid. Chlorinated which typically contain Perchloroethylene, Methylene Chloride or Trichloroethylene as the active solvent. Non-chlorinated which typically contain acetone, heptane, isopropyl alcohol, mineral spirits or toluene as the active solvent. The chlorofluorocarbon (CFC) that you refer to may be the propellant in the aerosol can.

You mention you haven"t observed any cracks after using brake cleaner on your records. Did you analyze your records with a high magnification microscope and look for micro cracks, pits or any changes to the record surface?

I don’t know the chemical composition of "LAST" record preservative, but the patents for record preservatives that I am familiar with typically list a perfluoropolyether as the lubricant in a suitable carrier. The purpose of these preservatives is to coat and lubricate the record surface and protect it from friction and wear from the stylus. These record preservatives are very different from brake cleaners and contain no chlorinated species and no chlorofluorocarbons (CFCs) that I am aware of.

@mijostyn

I have no association with LAST and I have never used it. I am just posting what I found on one of their patents and one of their brochures at the Consumer Electronics Show (CES) 1982.

One of the patents that I found was issued to Walter E. Davies, one of the founders of the LAST company. The patent states the following:

"Compositions for preserving records and reducing the friction thereon, have now been invented. Compositions for preserving records comprise about 0.05% to about 0.2% by volume perfluoropolyether having an average molecular weight of about 2,000 to about 6,000, such as Fomblin® Y25, and a perfluoroalkane carrier."

A quote from a LAST brochure at CES 1982:

"LAST effects a change in the surface of the vinyl to a depth of ~ 10 moleculer units which has the effect of reducing the surface free energy of the vinyl record which reduces friction and provides better traceability of the stylus."

Reducing the surface free energy makes sense if the active species is a fluorocarbon similar to the patents which describe using a perfluoropolyether as the lubricant.

@mijostyn

I never stated an opinion regarding the LAST record preservative. I have never used it or analyzed it. I only stated what they claim in their patent and brochure for your information regarding its chemical composition. You stated this in a previous post on 07-15-2023:

"LAST the record preservative is mostly if not entirely a CFC"

Their patent does not list the use of a CFC in their formulation. Their patent using a perfluoropolyether as a lubricant in a suitable perfluoroalkane carrier is not unusual. Perfluoropolyethers are widely used as lubricants in a variety of industrial applications, for example the Magnetic Recording Media industry where they are used as lubricants on HD drive surfaces. These coatings are typically only a few nanometers thick. In fact in my laboratory we analyzed several perfluoropolyethers which were coated to lower the surface energy of various substrates. Typically these coatings were between 1 to 2 nanometers thick. We had no problem characterizing these coatings with the proper analytical techniques. The LAST formulation can easily be characterized in a similar fashion to what I would typically do with the coatings in my laboratory. To determine the chemical structure, composition and thickness of these coatings I typically used several analytical techniques including: Photoelectron Spectroscopy, Static Secondary Ion Mass Spectrometry, Spectroscopic Ellipsometry, and Atomic Force Microscopy.

@mijostyn 

As I stated in a previous post these perfluoropolyether lubricants are typically only a few nanometers thick. Assuming the LAST record preservative is a similar thickness, you would not be able to see it on your slide.

@wizzzard

I never mentioned using an electron microscope for my analysis of perfluoropolyethers although I have used SEMs and TEMs as supporting techniques for other experiments. The main techniques that I used are Photoelectron Spectroscopy and Staic Secondary Ion Mass Spectrometry. Both techniques can easily detect coatings less than a few nanometers thick. In fact they can detect surface species as low as 0.01 of an atomic layer depending on the chemical composition of the coating. They would have no trouble detecting the LAST perfluoropolyether on a glass slide even if it was less than a molecular layer. Besides detecting sub atomic coatings, they can determine the chemical and electronic structure of the coating as well as a quantitative determination of the coating. Supporting techniques that I used and mentioned are Spectroscopic Ellipsometry and Atomic Force Microscopy.

@wizzzard 

I just read that you requested information from me. I do not know what information you requested. I must have missed it. 

@lewm 

The analytical techniques that I discussed in my last post were not used on vinyl records. We were discussing the analysis of perfluoropolyethers in the LAST record preservative formulation and how one could determine the chemical composition of the formulation. I just listed the analytical techniques that I had used to study perfluoropolyethers as lubricants on magnetic media in my laboratory. 

I did not operate or interpret the results from the supporting analytical techniques that I mentioned. These were operated and the data interpreted by colleagues in my laboratory.

My expertise is with Photoelectron Spectroscopy and Auger Spectroscopy.

The analysis I did on vinyl records was back in the late 70s when I built my first ultrasonic record cleaner. I primarily used Photoelectron Spectroscopy and Optical Microscopy to evaluate the effects of ultrasonic cleaning of vinyl records as discussed in my post on 06-21-2023 at 04:05PM.

Because you asked what I worked on. Some of my research entailed corona, plasma, ion beam, UV and gas phase modification of polymer surfaces, mechanistic studies of metal/polymer interfaces with relevance to adhesion, surface properties of self-assembled monolayers and surfactants, chemical and electronic properties of catalytic metal nanoparticles, characterization of the chemical and electronic structure of OLEDs.

@wizzzard

You asked for information about the commercial ultrasonic record cleaners. I am not familiar with any of the commercial ultrasonic record cleaners. I have no experience with any of them and I haven’t researched them. I built my ultrasonic cleaner back in the late 70s using a standard laboratory unit. The unit I used had either 1 or 2 transducers in the bottom and operated at 40 kHz. I do not know the power output. It had temperature control which I typically operated at between 36 to 38 degreed C. I fabricated a spindle assembly that could hold 10 records which rode on an adjustable track. I used it for over 30 years with excellent results so I had no reason to ever look at any of the commercial units. My focus when I built it included; the time in the bath, temperature of the bath and the bath solution (refer to details which I posted on 06-21-2023 at 4:05pm). I never investigated any variables in the ultrasonic unit itself.

I no longer have the unit because I went all digital about 13 years ago. I ripped all my CDs lossless to a music server and also digitized my favorite/hard to replace records. I eventually sold my turntables and sold/donated my record collection.

@lewm 

You are correct regarding the effectiveness of distilled or deionized water be itself in the ultrasonic bath. Refer to my post on 06-21-2023 at 4:05pm. 
 

i don’t know whether there is a right frequency or wattage but my experiments @ 40 kHz demonstrate that water alone in the bath is very effective in most cases.