Record Cleaning, A Comprehensive Resource

[phantomrebel]

The purpose of this thread is to review record cleaning strategies. There are many discussions about this topic as everyone has used, or at least heard of, a variety of methods and cleaning solutions from either manufacturers, fellow enthusiasts, or internet posts, yet often the logic behind the strategy is not thoroughly explained. I was approached to start this thread given my scientific background and my participation in the long record cleaning thread found here (discussion of topics in this thread remains welcome in this thread):

https://audiokarma.org/forums/index.php?threads/record-cleaning-youre-doing-it-wrong.689430/

That thread contains a lot of information from many sources that is buried among much discussion and commentary. The goal is to present summaries here, while continuing discussion there, so that we have a reference where folks can easily find information. Given my background, the discussion will focus on why things are done (e.g. which chemicals are used) as there are summaries of various treatments people have used elsewhere (for example, https://audiokarma.org/forums/index...of-fact-fiction-and-collective-wisdom.633407/ )

We will cover the gamut, from how our records were made and what is in them to discussing the typical contaminants found on our records and how they are specifically dealt with. As static charge also plays a role in contaminating records, dealing with this problem will also be discussed. Going forward, I will periodically post summaries of specific topics related to record cleaning and attach appropriate links, figures, pictures, and other references. Having this all in one thread will allow one to easily skip to the topic they are interested in.

As a fellow enthusiast, I love records and want to preserve them for future generations. There are as many ways to clean a record as there are ways to bake a cake so I will try to stick to general principles on how things work rather than recommend a specific device or solution. I hope this reference thread is useful in helping you choose a record cleaning strategy that works best for you!

Table of Contents:

Composition of Vinyl Records
Detergents Part I: Types
Detergents Part II: Properties
Detergents Part II: Properties - (continued)
Introduction to Detergents
Static Charge Part I: Prevention
Static Charge Part II: Treatment
Additives​

Disclaimer:
While I am a scientist, I am not a polymer or surface chemistry specialist and have relied heavily on other experts to obtain the information presented in this series. If you find corrections or omissions, please PM me and I will be grateful to include them.

 

[phantomrebel]

For the first entry in this series, I thought we’d start with some information about vinyl record composition since it is important to know exactly what we are cleaning. Specialty cleaners for things like wood floors, clothes, bathtubs, and windows were developed with deep knowledge of the actual substance being cleaned. Just like you wouldn’t routinely clean your carpets with bleach, we should be careful what we put on our records as they are a specialty product like none other.

Vinyl records aren’t merely PVC, but are a complex mixture of PVC and PVA polymers, stabilizers, lubricants, colorants, fillers, conditioners, and other additives. If we desire to preserve the record, we should be mindful of using cleaning methods that do not affect their integrity. A delicate balance exits between thorough cleaning and preservation. Added to this is the complication of requiring reagents that do not leave behind residues or negatively affect sound transmission. Hence, mild specialty detergents and purified, neutral solutions form the basis of good commercial record cleaning products as well as “self-made” solutions recommended by experts working at archival institutions. More details of record composition are presented below for reference. Keep in mind that every producer had their own proprietary resin mix so exact compositions are a trade secret.

Composition of Vinyl Records -

The thermoplastic resin used to produce vinyl (non-shellac) phonograph records consist mostly of polymerized vinyl chloride (PVC) and PVC/polyvinyl acetate (PVA) copolymers. The PVA addition (5-15%) allows for superior processing (stamp molding) and flexibility. While PVC polymers are somewhat stable, they are not compatible with certain chemicals. There are compatibility charts available (e.g. https://www.calpaclab.com/pvc-polyvinyl-chloride-chemical-compatibility-chart/) that can act as a guide as to what to avoid exposing to vinyl records. For example, acetone, while fine on metals or glass, has a “severe effect “ on PVC and hence should not be used as a record cleaner.

The total vinyl polymer is typically 75-95% of the record weight. The other 5%-25% are additives that are critical to the production, performance, and stability of the product. Most of these additives are not covalently bound; they are merely incorporated within the polymer matrix and therefore may be leeched out. The additives include:

Heat stabilizers:
Record production would not be possible without heat stabilizers that mainly function to neutralize the acid (HCl) generated at production temperatures. PVC has low thermal stability and degrades in a dehydrochlorination reaction at temperatures above 70 deg C (extruder temps are typically 155C and molding presses are typically at 120C). The reaction is autocatalytic: the released HCl catalyzes further breakdown. By scavenging the HCl gas released at pressing, the stabilizers also protect the press stampers from staining and etching, giving them a longer life.

In addition to heat, UV and pollution exposure can initialize this reaction over time so it is important not to remove these endogenous stabilizers. In fact, it has been shown aging of records can be monitored by measuring the amount of effective stabilizer remaining in the disc [1].

The stabilizers are typically metal salts of fatty acids or similar organometallic compounds (often called “metallic soaps”). The metals are typically lead, tin, barium and/or cadmium and the fatty acids are typically lauric or stearic acid. They typically make up 0.5-2% of the resin mix and often more than one type are added. Many of these compounds also act as releasing agents (lubricants).

Organophosphite esters may be added as co-stabilizers as they reduce the amount of heavy metal compounds needed in the record*. Other stabilizers (e.g. phenolic antioxidants) that protect the polymer during its useful life (e.g. free radical scavengers, UV protection) are sometimes also included.

The organometallic stabilizers are essentially the components that form soap scum in bathtubs and showers. Hence, it is reasonable when cleaning vinyl records to avoid household cleaning agents (including formulations containing Vinegar) that remove soap scum. Acidic cleaners, in general, might best be avoided so as not to promote the dehydrochlorination reaction, exhaust the amount of effective stabilizer, or otherwise reduce the useful life of the product. For similar reasons, acid-free record sleeves are strongly advised.

Lubricants:
It is customary to add a lubricant to the resin mix to promote the flow of the resin during processing. The lubricant is typically a hard wax, natural (e.g Carnauba or Montan wax) or a synthetic (e.g. distearyl amide type waxes). Fatty acid esters also served as lubricants (the cationic type doubled as “conditioners”). Lubricants typically comprise 1% or less of the resin mixture. The lubricant also promotes release from stamper. Some refer to these as “mold releasing agents”, but it should be noted that they are integrated into the resin mix, not something added to the stamper. Because the lubricant is evenly dispersed within the record, it also reduces friction at the finished record surface, for example, reducing heat and potential PVC breakdown as a stylus moves across. Hence, removal of lubricants is not desirable. Hard wax removal requires heat and/or strong solvents so these should be avoided (e.g. no steam cleaning). Additional friction at the record surface may result in audible noise: RCA found that too much or too little wax lubricant in their mix produced non-uniformity that resulted in noisy records [2]. Generally, 0.4-0.5% esterfied Montan wax (Wax E, Hoechst Corp.) was the most effective lubricant addition [3]. For best performance and lowest noise levels, we should strive to maintain the lubricant content of our records.

Colorants:
It is customary to add a colorant so that the record surface is more easily observed (for defects, etc.). Carbon black is the most common as it also offers durability to the product and it is typically included at 0.25 -0.5%. [4]. Carbon Black has the additional benefit of distributing electrical charges and increasing the rate at which such charges are dissipated (reducing static charge). Carbon Black is insoluble in water and most solvents so it is not something easily removed without destroying the record. Some resin recipes (transparent, colored records, and others**) deliberately omit carbon black from the mix and may add another colorant, often titanium oxide (white base) and/or a desired pigment colorant.

Fillers:
Some resin producers added fillers, mostly to reduce the amount of expensive virgin polymer they had to include but also for added wear resistance. All kinds of fillers have been used over time, everything from cellulose-derived products to diatomaceous earth, some producing greater background noise than others. The most common modern filler is recylcled vinyl. Because this vinyl has already been processed, any contaminants present get incorporated into the new vinyl product, often resulting in a noisy record. These contaminants are embedded within the vinyl matrix and are not easy to remove without damaging the record. Therefore, it is often recommended to purchase 100% virgin vinyl records. Most of the other fillers in old records are inert and not easily removed or effected by most cleaning agents.

Plasticizers:
Plasticizers change the viscosity and melting properties of the resin mix, improving moldability and flexibility of the final product. They essentially decrease the attraction between polymer chains allowing for a flexible record that is more resistant to breakage. For the most part, the PVA –PVC copolymer in the resin provides these properties when mixed with the PVC monopolymer. However, additional plasticizer compounds have historically been included in resin mixes for increased flexibility and durability. RCA used epoxidized soybean oil (ESBO) which has the added advantage in that it is also an HCl scavenger (stabilizer activity). Others have used traditional plasticizers, like phthalate esters. The amounts and types of included plasticizers vary greatly, depending on when and where the record was produced, but typically make up less than 1% of the mix (sometimes 0%). In the early 1970’s, there was a cost cutting move to make thinner, more flexible records and these included higher plasticizer levels; some even found toluene (up to 3%) allowed for thinner records [5]. Most of the added (non-polymer) plasticizers are solvent soluble. Studies by preservationists on PVC artifacts has shown plasticizer extraction with solvents, including alcohol (at concentrations 60% and higher) [6]. Hence, it is reasonable to keep alcohol (and other solvent) concentrations as low as possible in cleaning solutions. To maintain flexibility, durability and integrity of our records, we should choose solutions that do not affect their plasticizer content.

Conditioners:
A few producers included a conditioner in the mix to aid in lubrication and control static. The typical conditioners are quaternary ammonium salts with long fatty-acid derived chains (“quat.” surfactants) [2]. Many quats have the added benefit that they have biocidal properties. Resin formulations that include them result in records that have lower surface friction, lower potential for static charge, and resistance to microbial contamination. These properties can be neutralized by anions, so it is useful to avoid common household dish soaps and detergents that typically include the anionic detergent SDS. The quats on the surface can be replenished, or added to records that don’t include them, by including them in cleaning solutions. [7].***


References:
1. Pickett, A.G. and Lemcoe M.M (1959) Preservation and Storage of Sound Recordings, Society of Amer. Archivists.
2. “Disc record and method of compounding disc record composition”, (1974) RCA Corp., US Patent # 3960790
3. “PVC Molding Composition“ (1978) RCA Corp, US Patent #4168256A
4. "Conductive phonograph record containing thermoplastic resin and carbon black” 1961 Miller, H.B. US Patent #2997451
5. “Phonograph record composition and process” (1974) Sands, A., US Patent #3846361
6. Munoz C.M. et. al (2014) “A model for finding cleaning solutions for plasticized poly(vinyl chloride) surfaces of collections objects” J. Amer. Inst. of Conservation, 53 (4), pp. 236-251.
7. “Destaticized Phonograph Records And Methods For Producing Same” (1954) Monsanto, US Patent# 2680080



Notes:
*Lead-stearate was once used, supporting the notion that records can contain lead.

**One modern producer (the maker of Quiex SV-P) deliberately excludes carbon black from their resin mix as they claim : “Carbon Black contains trace metals that become magnetized and cause electrical distortions in cartridges during playback that smears the sound.” This claim is controversial.

***Quats are also the active component incorporated in antistatic sheets and anti-static record sleeves.

 

[phantomrebel]

Records vary in their level of contamination, but all typically require cleaning for optimal playback and longevity [1]. Even a new record has undergone some sort of handling and will possess some level of accumulated particles, static charge, or film. While there is a large variation in the type and amount of contamination found on records, the principles of cleaning are the same: we want to use a neutral solution that is mostly water (“aqueous”) and also includes a surface acting agent (“surfactant”) that reduces the forces that allow contaminants to stick to the record. Water alone, while a great solvent, is too polar and simply has too much surface tension to disperse and solubilize most bound contaminants.

Whether the terms, soap, surfactant, detergent, or wetting agent are used, they are essentially all describing the same class of chemicals: those with a polar, water-loving (“hydrophilic”) head group and a long, oily (“hydrophobic”) tail section. At specific concentrations, detergent molecules aggregate and form spherical “micelles” in aqueous solutions, where the hydrophobic tails sequester inside the sphere and the polar heads are exposed at the surface.

For soap, the tail sections were fats derived from animal sources. With advances in chemical synthesis, detergents arose with tail sections made from petrochemicals. The advantage of detergents is that a huge variety of types can be synthesized, combining different head and tail groups, giving each unique properties to suit a particular application. Hence, unique detergents are specified to do specific jobs in consumer cleaning products, industrial processes, and scientific experiments.

Selecting the best detergents for record cleaning relies on a number of factors. Foremost, we should consider the nature of what we are cleaning. As reviewed in the previous post, records are a very unique synthetic product. Contaminants must be removed from fine grooves embossed in a vinyl polymer in a way that does not remove or react with endogenous chemicals in the product, does not leave a film that effects amplified playback, and does not promote further contaminants to stick via residue or static charge [2]. Other considerations like availability, stability, cost, and safety also play a role.

There are many detergents that will satisfy these requirements, each with their advantages and disadvantages. Through experimentation, preservationists and manufacturers have identified several that do a very good job on vinyl and many have specifically recommended the use of alcohol ethoxylates (e.g. Tergitols) for record cleaning [3, 4]. To better understand this recommendation, and to explore the other types of record cleaning solutions people use, a deeper discussion of detergents is presented below and in a subsequent post (Parts I and II).



Detergents Part I: Types -


The major detergent classes are distinguished by the nature of their hydrophillic head, as this is the region that is exposed to water:

Anionic: These detergents have a negatively charged head, typically a sulfate group attached to the hydrophobic tail (e.g. alkyl sulfates). They are generally strong detergents with the most common being sodium dodecyl sulphate (SDS). They are relatively inexpensive so are the main detergents found in consumer products like dish soap and shampoo (where SDS is often re-named "laureth sulphate" for marketing purposes).

Anionic detergents are very effective cleaners, but vinyl preservationists are concerned that as strong detergents, they potentially extract stabilizers and lubricants from the record each time they are used [5]. The long-term effect of this is debatable for the average vinyl enthusiast. A short-term concern, however, is that they increase the potential for static charge build-up. The logic behind this is that vinyl records are insulators that have a natural tendency to accumulate a net negative charge (acquire electrons) and that adding a negatively charged surfactant to the surface compounds the problem. Another issue with some anionics is that they can form insoluble complexes or “scum” if the water is high in divalent cations like calcium and magnesium.


Cationic: These detergents have a positively charged head, typically an ammonium group attached to the hydrophobic tail. The major subclass of cationic detergents possess an ammonium group that is quaternary substituted and are often referred to as “Quats”. Quats are interesting surfactants as many have antistatic and antimicrobial properties. Hence, they are often found in consumer products like dryer sheets and hair conditioners as well as antibacterial hand soaps and bleach substitutes. Quats have been used to treat records since the 1950’s [6, 7] and were even incorporated into vinyl resins (e.g. RCA’s 317x “Miracle Surface”) [8-11]. Commonly used examples of these detergents are Didecyldimethylammonium chloride, Cyastat SN, and Benzalkonium chloride.


Non-ionic: These detergents have a polar head group that does not carry a charge (are neutral). The most common are alcohol ethoxylates, ethoxysulfates, and alkyl glycosides. They are often found in photographic wetting agents and gentle (or “Free”) laundry detergents. The lack of charge makes them weaker at attacking some contaminants, but this also makes them less likely to extract endogenous chemicals from records (or removing color from clothes). They also do not introduce any charge to the surface. For these reasons, they are the preferred choice of vinyl record preservationists [3,4]. Examples are Triton X-100 and the Tergitol 15-S series.


Zwitterionic: These detergents have both positive and negative charges on their head groups. Hence, they often share the properties of ionic detergents with intermediate strength and antistatic properties yet are net neutral like non-ionics. Though they work very well, their use on records is not widespread because they are hard for the average enthusiast to acquire in pure form. An example is cocamidopropyl betaine, which is often found in shampoo and bodywash (despite evidence that it is a skin irritant!).




Discussion:

Consumers exploit the properties of these detergent classes every day. For example, they wash their hair with an anionic detergent–based shampoo because it is strong at removing dirt and oils, then they treat it with a cationic-detergent based conditioner to neutralize charge and remove static frizziness. You can confirm this with the bottles in your shower by examining the first listed ingredients.

So why not just shampoo and condition our records? One could (and some do) but hair is a specific material that benefits from replenishment with natural oils, salts, proteins, gums, thickeners, preservatives, fragrances and other compounds that are not particularly desirable on a record surface. It is important to note that despite extensive shower rinsing, a small amount of these chemicals (a “molecular layer”) is left behind, bound to the hair fibers that leave the surface silky, shiny, and bouncy.

The same goes for records, where we’d like to leave the surface free of contaminants, residue, and static charge yet have to mindful that despite extensive rinsing, molecules will be left behind. In mass, the molecular layer of detergent remaining on a record can affect its properties. In addition to cleaning, Anionic detergents can leave a surface that is more prone to take on static charge. Non-ionic detergents can be neutral and even provide beneficial lubrication. Cationics can provide anti-static and anti-microbial effects. Combination of these different detergent classes might provide all the benefits without the drawbacks. Hence, when selecting a product or system for record cleaning, it is good practice to keep these general principles in mind.

The properties of specific detergents, and how they are used on records, will be explored in Part II of this topic.


References:

1. Fantel, Hans. "Pampered record can live to be 100." New York Times. Oct 10, 1976 ; pp 26-28.
2. Maier, Bruce. "In Search of the Perfect Record Cleaner." High Fidelity 22 (9) , Sept.1972, pp 52-55.
3. http://www.loc.gov/preservation/care/record.html U.S. Library of Congress
4. St-Larent G. (1991) :”The Care and Handling of Recorded Sound Materials” CLIR Reports Sept. 1991. Music Division, National Library of Canada.
5. Pisha, B.V. “Record Cleaners Revisited”. Audio Magazine, May 1976. p.40.
6. “Destaticized Phonograph Records And Methods For Producing Same” (1954) Monsanto, US Patent# 2680080
7. Sherr, A.E. and Vitalis E.A. [aff. Amer. Cyanamid Co] (1963) Ind. Eng. Chem. Prod. Res. Dev. Vol.2 No. 2 pp. 97-102.
8. Humfeld, G.P. [aff. RCA] (1962) “Control of Static Electricity on a Phonograph Record” J. Aud. Eng. Soc. Vol.10, 290-293.
9. Victor Co. of Japan, Patent # GB969636A. (using Cyastat SN).
10. Humfeld G.P (1960) ”Antistatic Phonograph Records” RCA Engineer Vol 6 No.3 Oct-Nov pp.18-20.

 

[phantomrebel]

Detergents Part II: Properties -


Dependent on the chemical composition of the water-attracting (hydrophilic) head group and oil-attracting (hydrophobic) tail group, detergents vary with respect to their size, strength, stability, solubility in water, number of molecules per micelle, concentration/salt/pH/temperature dependence, foaming characteristics, cloud point, rinseability, purity, toxicity, and effectiveness towards specific contaminants.
Knowing that we wish to clean a wide variety of contaminants from a vinyl polymer surface at room temperatures using neutral, aqueous, salt-free solutions greatly narrows the field. In this section the properties of specific detergents and consumer products that are frequently used in record cleaning are discussed.


A. Pure products:

Selecting pure ingredients allows ultimate control of what goes on to our records. It also allows for adjustments in ratios to other cleaning solution components to suit a particular application. For examples, less detergent is required when using an ultrasonic tank versus hand-washing and more detergent may be required for particularly dirty records. Another advantage is cost, as a small bottle of concentrated pure detergent can be enough to clean an entire collection of records. The downside is that these reagents are not stocked on the supermarket shelf and one has to seek them out. Furthermore, as with baking or cooking, one needs basic mixing and fluid handling skills and equipment. The most widely used detergents in record cleaning are:


1. Tergitol 15-S series (Dow Chemicals) [1]. This series of Tergitols are versatile, biodegradable, non-ionic detergents based on secondary alcohol ethoxylates. They all have the same tail, an up to 15 carbon atom long, Secondary substituted alcohol (= 15-S). They differ in the degree of ethoxylation (number of hydrophilic ethylene oxide groups at the polar head). Hence, 15-S-3 contains 3 ethylene oxide units and 15-S-9 has 9. Given this, one can conclude the S-3 is more hydrophobic (has less polar content) than the S-9. Not surprisingly, 15-S-3 is more active against oily contaminants than S-9, but it isn’t soluble in water. 15-S-7 is right in the middle of being water soluble yet active against oils while maintaining good rinseability and is therefore a great choice for record cleaning [2]. It’s cloud point (37 C) is also just above the temperature where it is typically used which is also advantageous.* That said, some people combine S-3 with S-9 to get a soluble mixture, with the goal of having a cleaner that is active towards a broader range of contaminants. The only drawback here is that excess S-3 will adhere stronger to the record (via hydrophobic interactions).

The United States Library of Congress recommends a solution of Tergitol 15-S-7 for cleaning of old phonograph records whereas the Canadian Conservation Institute recommends a mixture of Tergitol 15-S-3 and Tergitol 15-S-9 [3]. An acceptable range of Tergitol in cleaning solutions is 0.01-0.1%. The higher range would be for hand-cleaning, lower in the range is used in mechanical cleaning devices. Tergitols are useful in ultrasonic cleaning tanks as their foam is low and collapses rapidly.



2. Triton X series (Dow Chemicals) [1]. This series of Triton non-ionic detergents are based on octylphenol ethoxylates. They are similar to the previously discussed Tergitols except their tail group is an aromatic hydrocarbon (substituted phenol) rather than a branched secondary alcohol.
Like the Tergitols, they are distinguished by the number of repeating ethylene oxide groups they have attached at the head end of the molecule. For X-100, this is an average between 9 and 10 units; For X-114, it is 7 to 8 units, and for X-102 it is 12 units. The X-102, though useful, is not widely available so is rarely utilized in record cleaning. Due to the smaller polar region, X-114 has a higher critical micelle concentration and lower cloud point than X-100. Hence, you need to use higher concentrations of X-114 and use it at cooler temperatures (under 22 deg C) to maximize detergency and avoid phase separation. X-114 is also difficult for the average enthusiast to obtain. For these reasons, Triton X-100 is a preferred detergent for record cleaning.

While relatively stable, Triton X-100 is best stored tightly capped in a cool, dark place so as to avoid oxidation (peroxide formation). The concentrate is quite viscous and dissolves into water very slowly. To make solutions, one can mix for several hours on a stir plate, heat the solution, or premix in a solution of 50% alcohol. It should be noted that there is evidence that octylphenol ethoxylate detergents like Triton X negatively effect aquatic environments. Biodegradation produces a toxic aromatic hydrocarbon product (from the released tail group) that mimics estrogen and messes with reproductive systems. For these reasons, the EU is set to ban their use in 2021 [4]. This ban will likely also include Tergitol NP-9 as it is essentially the same as Triton X-100 so European enthusiasts will have to use Tergitol 15-S-7 or other non-ionic detergents going forward.



3. Other non-ionic detergents: Serveral other non-ionic detergents are available that can be substituted for Tergitol or Triton in record cleaning and used at similar concentrations (0.01-0.05%). There is a group of non-ionic detergents known as polysorbate esters have been used in record cleaning. Tween-20 (Polysorbate-20) and Tween 80 are common examples. These detergents are very gentle yet can be effective at very low concentrations. They are somewhat difficult to find and are subject to oxidation and mold growth so need proper storage.

In some areas one may come across the Pareth line of detergents which is just another name for Tergitols: C11-15 Pareth-7 is the same as Tergitol 15-S-7; the Pareth-9 is Tergitol 15-S-9, and so on.

The surfactants under the names Marlipal, Brij, and Neodol are similar alcohol ethoyxylates with a linear fatty alcohol tail (often derived from palm or coconut oil) attached to varying length ethylene oxide heads.

In an effort to supply more eco-friendly detergents, Dow has produced the Ecosurf line. Ecosurf EH-6 has very similar properties to Triton X-100 with added advantages of low, short-lived foam, excellent wetting and detergency, combined with safe biodegradability. The only drawback to the average enthusiast is that it is somewhat difficult to obtain at this time.

Another important class of non-ionic surfactants are amine oxide based. This group includes surfactants like lauryldimethylamine oxide (LDAO). These surfactants actually become cationic under acidic conditions and they decompose at high temperatures (>90 C). Although they are present in many consumer cleaning products, they are difficult to obtain in pure form for the average enthusiast but definitely worth seeking out as they clean and rinse away very well.

When using any of these detergents on records, a good starting point is to use a solution of 0.01 to 0.05% in water.


4. SDS: By far the most common anionic detergent used is sodium dodecyl sulfate (SDS, or sodium lauryl sulfate). It consists of a long chain alcohol tail (lauryl alchohol, often derived from coconut or palm oils) that has a sulfate (SO4-) group at the head. It is a strong detergent and solubilizes a wide range of contaminants, though it is most effective in removing particulate soils (hence its ubiquitous presence in laundry detergent and shampoo). It exhibits significant foaming, precipitates at cold temperatures, and its properties are affected by salt concentration and pH. Because it is anionic, residual detergent molecules will leave a negative charge on the record surface after deionized water rinses. It is obtained in relatively pure form as a solid (preferably as micropellets to avoid breathable dust) that must be dissolved in warm water.

A similar detergent is sodium lauroyl sarcosinate (Sarkosyl). It is a bit milder than SDS and is more soluble at cold temperatures. Both detergents are typically used in the range of 0.01-0.025% for record cleaning. SDS should not be used in ultrasonic tanks due to excessive foaming. Due to the charge left on the record by anionics, it is recommended they be air-dried after cleaning as opposed to rubbing with a towel to prevent static build-up. Another tip is to follow a SDS wash with a quat wash, much like following a shampoo with a conditioner.


5. Quats: Quaternary ammonium surfactants (Quats) are common surfactants used in a variety of applications including record treatment and cleaning. Though they often exhibit mild detergency, they have additional biocidal and anti-static properties that make them attractive as components of record cleaning solutions. Examples commonly available for DIY cosmetic formulations like dicetyldimonium chloride (Quaternium-31 ) and cetrimonium chloride are often successfully employed in record cleaning at concentrations typically under 0.05%. Pay attention, however, that few of these are sold as 100% product and dilutions must account for this. Quats that are only soluble in oil should be avoided as they leave a waxy residue on the record surface. The water-soluble examples are some of the best reagents one can use for record cleaning, especially when they are combined in a solution with non-ionic detergents. In this case, they can be reduced to final concentrations in the 0.005-0.01% range since the non-ionic does the major cleaning and the quats are present for their antimicrobial and antistatic properties. This strategy particularly suits RCM devices, as the cleaning liquids are often difficult to completely remove from tanks and tubing that otherwise can get moldy.


*Non-ionic detergents have a cloud point or temperature where detergent and water separate (for maximal detergency, we want to be close to this). Mixing ionic detergents with non-ionics raises their cloud point.


.....

 

[phantomrebel]

Detergents Part II: Properties - (continued)

B. Commercial/Consumer products

Not everybody has access to pure detergents or desires to mix ingredients so they turn to off-the-shelf solutions. In these instances, it is important to know what detergents they contain so educated decisions can be made. One issue however, is that exact formulations are proprietary so that even if the detergent is listed, it is usually disguised using unusual nomenclature and/or listed as a range of possible concentrations. Furthermore, inert or proprietary ingredients are rarely specified so we don’t know exactly what we are putting on our records. There are a few products, however, that are nevertheless widely used in record cleaning:

1. Photo-Flo (Kodak). There are many references to the use of Photo-Flo as photographers logically extended its wetting properties to treating records. It works because Photoflo is a source of non-ionic detergent. Specifically, Photo Flo 200 is a mixture Triton X-100 (5-10%) with polypropylene glycol (25-30%) [5]. Hence, the majority of the solution is the glycol, originally included as a humectant to allow even drying and eliminate streaks/water spots on photographic films. Photo-Flo 600 is similar, with a higher concentration of Triton (25-30%) and with ethylene glycol (35-40%) [6]. Some might not want these glycols on their records (or around their pets). There are more suitable photographic products like Ilfotol , which contains non-ionic detergent (<2.5% C12-15 alcohol ethoxylate, e.g. Neodal 25) with a preservative (1.5% phenoxyethanol ) [7] or, even better, the concentrated Edwal LFN wetting agent that simply contains non-ionic detergent (35% alcohol ethoxylate) in isopropanol (15%) [8].
For record cleaning, the stock products are diluted accordingly to reach final non-ionic surfactant concentrations in the 0.01-0.05% range.


2. Jet Dry (Finish). Jet dry dishwashing rinse aid is sometimes employed as a surfactant in record cleaning. It works because it contains 10-30% non-ionic detergent (C12-15 ethoxylated alcohol) . However, it also contains up to 5% citric acid and up to 5% Sodium cumenesulfonate among other chemicals (9). The acid gives the product a low pH (<3), though this becomes more neutral as the solution is diluted. Hence the product is shunned by purists, who prefer not to expose their vinyl to acidic conditions (see previous Record Composition section). Furthermore, the cumenesulfonate, while a useful hydrotrope, is anionic and might contribute to static build-up. To get in the 0.01-0.05% detergent range, the product is diluted 1:1000 (1 ml per liter).


3. Dawn (P&G). Many people simply add a drop of liquid dish soap to their record cleaning solutions. The most popular brand is Dawn, an aqueous mixture of mostly anionic detergent (SDS) along with lower concentrations of non-ionic detergents (C10-C16 amine oxides and Pareth), alcohols, salts, stabilizers, polymers, dyes, and preservatives (10). Dish soap products are not favored by record preservationists due to the presence of SDS and the extensive mix of additional chemicals (even in the “Pure” or “Free” versions). However, they are still used by hobbyists and as they contain 20-30% detergent they are typically diluted 1000-fold or more in record cleaning solutions. The same precautions mentioned above for pure SDS solutions (above) apply.


4. Hepastat 256 (Brighton). This is a commercial cleaning product consisting of mostly cationic detergents (21.7% mixture of various quats), non-ionic detergents (6% alcohol ethoylates), alcohol (2.8% ethanol), and chealator (3% EDTA). There are many similar “256 Quat” products (e.g. Virex II 256, Maxima 256, Spartquat 256, 3M Quat, Chlorox professional quat, etc) that are meant as disinfectant cleaners for hospitals and institutions and used at 1:256 dilution. For record cleaning, they are used at 1:1000-1:2000 dilution which still provides adequate cleaning as well as anti-microbial and antistatic protection. Adding a small amount of these quat cleaners to a non-ionic detergent mix can be quite beneficial. However, these products should NOT be mixed with anionic detergents as they interact, become ineffective, and sometimes form precipitates.


These are a few of the more common commercial products that have historically been used on records. A complete list of consumer products used to clean records would be too extensive to categorize and list every ingredient. I will leave it to the user to look up a particular product, find the ingredients, and determine their potential benefits and shortcomings based on the information here and elsewhere. However, be aware that there is great risk in using a household cleaning product on phonographic records since NONE of them have been designed or tested for this purpose. That said, people will do what they do so a few guidelines are helpful when accessing a potential product for record cleaning:

• Understand the type of detergent(s) that are included and their properties.

• The fewer non-detergent ingredients in the product the better.

• Know the concentration of detergent the product contains and dilute appropriately.

• The more concentrated in detergent the better as undesirable secondary ingredients are diluted out in working solutions.

• Pay attention to the pH of the product. Some may contain the desired detergents but are caustic and can do harm.

• Try the product on unimportant records first.

• Examine both the appearance AND sound quality of the cleaned product over an extended period of time.

• Pay attention to the development of static charge.

• Pay attention to stylus condition (e.g. build-up) after playing.

• When in doubt, simply DO NOT USE IT.

References:

1. There are several other series of Tergitols (NP, L, X, etrc. ) that have different chemical composition and properties. We focus on 15-S series because they are commercially available and have been specifically used on records by preservationists. See http://msdssearch.dow.com/PublishedLiteratureDOWCOM/dh_09b0/0901b803809b0065.pdf
2. Originally developed by Union Carbide, which was acquired by Dow . see http://img06.b2b.hc360.com/pic-6/handbook-pic-1/6-1-734861.pdf
3. https://cool.conservation-us.org/byauth/st-laurent/care.html
4. https://cepad.cefic.org/images/Documents/CEPAD-FAQ-on-Authorization-of-NPE-and-OPE-17-July-2017.pdf
5. https://intranet.ssp.ulaval.ca/cgpc/fsss/fichiers/Photo-Flo.pdf. Note, p-tert-octylphenoxy polyethoxyethyl alcohol = Triton X-100
6. https://www.freestylephoto.biz/pdf/msds/kodak/Photo_Flo_600_Solution.pdf
7. https://www.ilfordphoto.com/wp/wp-content/uploads/2017/04/Ilfotol-EN-H17-44-10256.pdf. Note that Ilfotol was re-formulated to eliminate the previously included isothiazol preservative.
8. https://www.digitaltruth.com/products/edwal_msds/Edwal_LFNWettingAgent_MSDS.pdf
9. https://hpd.nlm.nih.gov/cgi-bin/household/brands?tbl=brands&id=18001742
10. https://hpd.nlm.nih.gov/cgi-bin/hou...nds&id=16030686&query=dawn&searchas=TblBrands

 

[phantomrebel]

Introduction to Detergents-

It was suggested that a basic, illustrated introduction to detergents might be useful and I apologize, I should have posted this before the in depth discussion above, but here we are. Let’s go back and try to understand what these surfactants are all about, starting with H2O, or plain old water, as it is the basis for all our washing solutions.

Water is an amazing molecule. It is said to be “polar” because it has a distribution of charge (due to the distribution of negatively charged electrons) where the two hydrogen atoms are partially positively charged while the oxygen is negatively charged:

The result is a polarized molecule that can be thought of like a magnet, where opposites ends have opposite partial charge or poles. Like magnets, the oppositely charged ends are attracted to each other, where (d-) oxygen atoms from one water molecule like to hold hands with (d+) hydrogen atoms from other water molecules. This is the basis for “hydrogen bonding”:

This hydrogen bonding force is strong and it dictates the behavior of water and everything it interacts with. It all works out if you are a water molecule in the middle of a solution as you have many partners to bond with and be happy. However, at the surface of a solution (the liquid-air interface) there are only partners on the inside, so these water molecules pull towards the middle, minimizing the exposed surface. The result is spherical water droplets, and the phenomenon at the surface where there is tension from these unbalanced forces is known as “surface tension”:

Because of the strong hydrogen bonding with itself, water exhibits higher surface tension than most liquids. It also is responsible for the relatively high boiling point of pure water. It takes a lot of energy to break their hand-holding. Water will also form strong hydrogen bonds with other polar molecules, which makes it a great solvent.

When another molecule doesn’t like to share because it has an equal balance of charge within itself (no “poles”), it will not join in with water. These “non-polar” molecules, oils for example, are referred to as “hydrophobic” (literally afraid of water). It is why water beads up on a waxed car or on the surface of our records and why oil and water do not mix: the water molecules hold together amongst themselves as do the oily molecules and you get segregation.

But what if a molecule has both polar and non-polar regions, how would it interact with water? Indeed, such amphiphillic molecules like this exist and they interact with water at the surface through their polar groups:

These compounds are called “surfactants” because they act at the surface and result in lowering the surface tension of water. Soaps and Detergents are the most common surfactants and man has learned how to make an endless variety of them. As mentioned previously, they all consist of a polar or hydrophilic “head” attached to a non-polar, hydrophobic “tail” structure:

Depending on the detergent, the water-loving (hydrophilic) polar head group can be positively charged (Cationic), negatively charged (Anionic), neutral (Non-ionic) or carry both positive and negative charges (Zwitterionic).

They all behave similarly in solution, where, dependent on their concentration, they exist in a balance between free floaters (“monomers”) and associated groups, as the hydrophobic tails spontaneously aggregate with one another to separate themselves from the water they hate. These organized surfactant aggregates are called “micelles” and they form a sphere stabilized by the fact that their non-polar tails are happily associated in the core while their polar groups are exposed at the surface, happily hydrogen bonded with water:

The concentration of detergent at which micelles start to form is called the Critical Micelle Concentration or CMC. At the CMC, when micelles just start to form, the surface is saturated with detergent and it is the point of maximal reduced surface tension. The CMC is different for every detergent as it depends on many factors like how long the tail section is, the chemical nature of the head group, etc. You can imagine that large, branched tail molecules would pack together in the core differently than small straight ones, for example. These factors also affect other characteristics, like the number of detergent molecules the average micelle contains (the Aggregation Number) and the lowest temperature at which micelles will form (the CMT = Critical Micelle Temperature). *

The CMC value is important to know, as it is a guide to detergent hydrophobic binding strength. The lower the CMC, the stronger the binding to oils. The lower the CMC, the more stable the micelle. Also, a maximum in foamability is reached around the CMC so a lower CMC means that less surfactant is required to produce foam. On records, we like to use detergent concentrations just above the CMC to ensure enough, but not too much, is present.


So what happens when this water-detergent solution comes in contact with our dirty records? The first thing is that the solution spreads across the surface since the detergent reduces the surface tension of water. Next, the hydrophobic tails associate with similarly hydrophobic regions of greasy contaminants and due to their polar heads, they make the contaminants more attracted to water. As more detergent molecules adsorb in this fashion, the contaminant gets dislodged from the record and surrounded by detergent molecules in the solution (trapped in a new type of micelle). Further pressure from detergent monomers keeps the contaminant from adhering back on the record so it is rinsed away with the water.

To do this process effectively, the surfactant must be a good wetting agent (lowering the surface tension of water so the solution spreads and penetrates), emulsifier (adsorbing to the contaminant by mixing its tails with the hydrophobic parts of the contaminant), dispersing agent (engulfing the contaminant in micelles and spreading them out in solution), and detergent (helping remove the contaminant in the wash). Some surfactants are good at one function like wetting and bad at another like dispersing and visa versa. This is where a mixture of surfactants comes in useful and why your laundry detergent contains a large variety of them (along with many other chemicals). The detergents we select for record cleaning are typically non-ionic and average at doing all these functions. In fact, some are mixes of molecules having a range of hydrophobicity, each with its strengths and weaknesses that complement each other.


I hope this helps you understand some of the basic concepts I previously mentioned and appreciate why it is so important to choose the right detergents for cleaning records. Combined with the knowledge of vinyl composition, these principles are the foundation of most commercial record cleaning solutions. That said, every record has a different set of contaminants and may require different treatments. More on this, and ways to deal with it, in a future installment.







*The Cloud Point is another temperature related property that is specific for non-ionic detergents. As temperatures pass the CMT, the non-ionic detergents become cloudy and separate into a detergent-rich and an aqueous layer, a process known as phase separation. This temperature is known as the cloud point.

 

[phantomrebel]

Static Charge (Part I)-

One of the biggest issues confronting phonograph records is their propensity to hold a static charge, which in turn attracts debris and leads to surface noise upon playback. A truly clean record is not only free of physical contaminants, but also it must be free of static charge. Fortunately, this issue can be dealt with by a variety of means, discussed below. Firstly, however, it is useful to understand the nature of static charge and how it arises.

All matter is made of atoms. Atoms have a nucleus of positive charge surrounded by clouds of electrons with negative charge. In the lowest energy state, these charges are in balance. However, with some energy input, the loosely held electrons can move or transfer energy from one material to another, creating materials with opposite net charges. This can occur when two materials are put in contact with one another and then separated, leaving the materials with a “static charge” [1].

​

The ability of a material to surrender its electrons or absorb excess electrons is a function of its conductivity. Our records, made mostly of PVC, are non-conductive (=insulators) so they take up charge easily but have little ability to dissipate it once the balance is disrupted by friction, heat, or pressure. Some materials tend to give up electrons and become positively charged while others tend to collect electrons and become negatively charged. The comparative tendency of a material to charge positive or negative is represented in the “Triboelectric Series”.

​

Within this series, PVC and related polymers are ranked negative as they tend to take on electrons. Therefore, when a vinyl record becomes in contact with, then is separated from, a material like a paper sleeve, it can become negatively charged [2]. Without getting into physics and Coulomb’s Law, suffice it to say that nature likes to balance charges so positively charged particles like dust are attracted to this negatively charged insulator. Hence, you end up with a dirty record with particles adhered via electrostatic forces. We observe that these forces are stronger than gravity as even large particles do not merely fall off. Fortunately, there are simple ways to overcome this phenomenon or prevent it from occurring in the first place.

Preventing static build-up:

I often hear from people who battle with issues from static electricity on their records and find that much of the problem is of their own making. They wash their records with anionic solutions, store them in paper sleeves, play them on a leather mat on an improperly grounded turntable, and perhaps live in a dry home with wool rugs. Science can help provide some insight into how these practices can lead to issues with static and how we can avoid them:

1. Handling. The surface area of contact, pressure, and speed of separation affect the amount of charge transferred between two materials. Hence, it is recommended that records should be removed gently and slowly from sleeves and that sleeves should be made of a material of similar triboelectric ranking (e.g. polypropylene) [3]. It is further beneficial if these sleeves contain or are treated with antistatic agents (discussed below). To a lesser extent, bending or distorting a material can also cause uneven charge distribution so keep records flat (relaxed) when removing from a sleeve or turntable mat. Dry wiping of records with any material should be avoided, unless this is a conductive material that leads to a ground. Our bodies can also carry charge so it is good practice to touch a ground before handling a record or equipment.

2. Humidity. Water can help conduct electricity as its polarity (discussed previously) allows it to contain or solvate ions. Hence, static build-up is less likely to occur in a humid environment. Prevention can be as simple as humidifying the listening space or as sophisticated as chemically attracting water molecules to the record surface. A humid environment is required for antistats to be effective and It also reduces the risk of electrostatic discharges (ESD) that can damage equipment.

3. Isolation/grounding. The turntable mat should be made of a material that is close to PVC on the Triboelectric series as records are continually placed in contact with, and separated from, this surface. Unfortunately, some manufacturers only consider sound deadening and have ignored this important detail (leather and felt, for example, are on the positive end of the series near fur). The turntable should be grounded so that any charge generated by the mechanics have a path to ground. Some turntable designs are particularly prone to static generation as they rely on materials on opposite ends of the Triboelectric series in constant frictional contact that are insulated from ground. Antistatic mats and pads are available, but they only effect the side in contact since the record is an insulator (no conduction path for charges on the opposite surface). Similarly, conductive brushes whether part of the cartridge or on a separate device are useful but they only effect the surface they are in contact with.

4. Ion balance. As anions and cations help neutralize charges, it is important to maintain a balance of them on the record surface. The chemicals we wash or treat our records with can affect their ability to acquire a static charge. This is particularly true in an environment where de-ionized water is used in washes (to avoid mineral deposits). As PVC polymers inherently take on a negative charge, we should avoid introducing excess anions or using agents/exposures that encourage PVC breakdown and chloride generation.

 

[phantomrebel]

Static Charge (Part II)-

Treating static build-up:

Once a static problem is encountered, it can easily be overcome. A variety of anti-static treatments and devices have been developed with primary application in industry where static charge can lead to contamination, product degradation, component damage, and even explosions. As the force is identical, we can adapt these methods to controlling static on our phonograph records.

1. Ionization. A charged record will attract ions (not just dust) from the air to neutralize the charge. Several devices are available that emit charged ions into the air. The most famous is the Zerostat gun, which generates positive and negative ions as piezo electric crystals are bent with the pull and release of a trigger. The functional concept is simple, as the charged record will attract whichever ions are required to balance the charge while repelling the others. However, if used improperly, the device will have no effect or even charge records up to the opposite polarity [4].

Other devices that rely on ionizing radiation (e.g.Polonium 210-based) are less prone to user error, but need frequent replacement due to the isotopes limited half-life [5]. Ionizing fans and bars are also useful and easy to find, but they require constant power and the good ones are expensive. Any of these devices can be successfully applied to neutralize static charge on records, provided they are used properly.

2. Dissipative brushes/pads. Another way to deal with static charge is to dissipate it using a conductive material. Carbon is such a material and has the advantage that it can be formulated into fibers and used in brushes to sweep the record surface, removing dust and static at the same time. One issue with these brushes is that their ability to remove static is limited by their inherent resistance which leads to incomplete charge neutralization. Individual carbon fibers are brittle so are braided or combined in a composite to a limited diameter, effecting their ability to get deep into the record grooves. The most effective brushes are manufactured in a way that has path to the handle (or a strap) so that charge can dissipate, with the user serving as a charge sink or path to ground [6].

Other brushes made of fine natural or synthetic hairs are also effective, some containing antistatic chemicals (e.g. quat-coated hairs) or interwoven with a highly conductive material (e.g. Thunderon®) [7]. These same materials can be effective when incorporated into turntable mats or stand-alone pads. Keep in mind that brush treatments offer no lasting antistatic protection; treated records must still be handled carefully so as not to re-introduce a charge imbalance.

3. Chemical antistat treatment. Chemicals that have antistatic properties are often used in industry and at home. The most common are the quaternary ammonium salts, especially the previously mentioned “quat” surfactants. Think of them functioning as a dissipative path from their carbon tails adhered to a surface to their polar head group that is hydrogen bonded to conductive water from the air. Hence, they are most effective in humid environments. Many commercially sold antistatic record cleaners, groove lubricants, and record conditioners consist of these compounds.
There are also home-made treatments. Antistatic sprays or sheets made for commercial “clean room” or household purposes contain quats, but they are not recommended for use on vinyl as they often contain additional chemicals (e.g. oils or solvent propellants) that can leave residues or potentially damage records. They are useful for treating carpets, furniture, and cables within the listening space however. Safe solutions of quats can be made (using pure cetrimonium chloride or cleaning mixes like Hepastat for example) and used alone, or as part of a cleaning solution, to provide antistatic protection. Keep in mind that while quats offer long term antistatic protection, they are not permanent and are subject to removal through wear or subsequent washing. Quat compounds are also effective antistats when incorporated into record sleeves or turntable mats.

Notes:

[1] There have been a lot of recent developments that make this traditional model of static charge a gross over-simplification. Recent research actually indicates that whole molecules, not just electrons or energy are transferred (see http://www.wired.com/2011/06/how-static-electricity-works/). Additional research indicates that it is the bending of molecules on the surface that actually releases the charge energy (see http://edgy.app/researchers-unravel-the-mystery-of-static-electricity).

[2] Note how polypropylene is rated similarly to PVC in this series, a reason sleeves of this material are popular among collectors.

[3] PVC sleeves should be avoided as they will interact with the PVC record over time (“like dissolves like”, particularly since the sleeves contain additional plasticizer), leaving uneven and audible polymer films on the record surface. The BBC collection and many private collections have suffered due to their use.

[4] see http://amasci.com/emotor/zerostat.html

[5] One device is the “StaticMaster” which is a brush with bristles that lead to a handle filled with radioactive Polonium-210 ceramic beads. Polonium 210 element emits alpha particles (positively charged Helium atoms) from its nucleus that collide with molecules of air, thereby creating a balanced supply of oxygen and nitrogen ions sufficient to neutralize both positive and negative static charges. However, its effective life is only 1-year given the 138-day half life of Po-210 (replacement cartridges are available). The device, developed in the 1960’s by Nuclear Products Company (El Monte, CA), is legal to sell as, under Nuclear Regulatory Rules, it contains less than 500 µCi of the isotope. Amstat (Mundelein, Illinois) sells these brushes along with similar spot ionizers that can be attached to the turntable.

[6] One of the more popular carbon fiber brushes, made by Audioquest, was redesigned to achieve this conductive path.

[7] Thunderon® (developed by Nihon Sanmo in Japan) is a material with very fine (0.0015 diameter) acrylic or goat hair fiber chemically bonded with copper sulfide. The material is incorporated into brushes by Gordon Brush and pads by Furutech (SK-X-III), for examples.

 

[phantomrebel]

Additives -

So, you have your wash solution of non-ionic detergent in de-ionized water and want to tweak it a bit to improve upon the formula for a specific application or condition. Here are some common additives used in record cleaning solutions:

1. Alcohols -
When to use: Most common alcohols, by themselves, are not good cleaners. They evaporate too quickly to allow for effective removal of contaminants. However, it is common practice to include a small amount of alcohol in record cleaning solutions as it can aid in solubilizing certain contaminants and also keep the detergents blended in solution. Note, this is for vinyl records: alcohols are NOT to be used on shellac records as this material is dissolved by alcohols.

What to use: For vinyl-based records, a variety of alcohols can be used, with ethanol and isopropanol the most common. The choice usually comes down to availability, but purity should also be considered. Rubbing or denatured alcohols are not recommended as these products contain additives like acetone, methanol, pyridine, benzene, and isobutyl ketone that are not desired in record cleaning. Additionally, even “purified” preparations of alcohol can contain contaminants. As they form stable azeotropes, they fractionate along with industrial water and other chemicals making it far more expensive (requiring more energy) to produce highly purified alcohol solutions. For record cleaning, it is best to find the highest concentration available. This is typically 95 to 99% isopropanol or ethanol. Of the two, ethanol is often preferred because it has less odor, is less toxic, and is compatible with a wide variety of solutions.

How to use: If you do choose to add alcohol, it is advisable to include it in cleaning solutions at concentrations of less than 20%. There is little benefit in adding more and it can actually cause harm by leaching or removing components of the vinyl matrix leaving the surface “dried out” and even noisy (see Record Composition section above for more on this).

2. Chelators-
When to use: Chelators are generally agents that bind and sequester metal ions, typically cations like calcium, magnesium, and iron. As these ions are present in tap water and cause mineral deposits, a chelator can be useful in their removal from such solutions. A chelator might be used, for examples, to follow a rough sink wash or after an enzymatic treatment that was done using water containing minerals. Additionally, these ions can stabilize aggregates of contaminants present on the record surface so by chelating them, the contaminants are more easily solubilized and dispersed, thereby aiding the detergent action in wash solutions.

What to use: The most common chelating agent is Ethylenediaminetetraacetic acid, or EDTA. While there are several forms of this chemical available, it is best to seek out the tetrasodium form of EDTA as it is soluble in water without having to adjust the pH of the solution.
How to use: It is advisable to use at low levels of EDTA in record cleaning solutions, typically in the sub-millimolar range (1 mM is ~ 0.38 gm/L). This is because the agent is known to be active against metal soaps (hence their inclusion in commercial limescale cleaners) and, as discussed in the Record Composition section above, such chemicals are present in the record matrix as stabilizers that we do not want to deplete. EDTA is typically added to a cleaning mix from a concentrated stock solution (a sterile 100 mM EDTA stock is stable for many months).

3. Flocculants-
When to use: Flocculants function to sequester debris, bringing suspended contaminants out of solution in a gel-like precipitant. Hence, they are typically used in a tank- or vessel-type washing apparatus, the most popular being the Spinclean, where contaminants become sequestered in the bottom of the tank.

What to use: Aluminum chlorohydrate and aluminum (or ferric) sulphate are commonly used to remove particles suspended in the aqueous solutions. These same reagents are used by water treatment plants and by pool /spa servicers to clarify water.

How to use: Flocculants are added to cleaning solutions at concentrations of 0.01% or lower. Commercial liquid pool flocculant solutions are typically 30-60% flocculant so should be diluted accordingly. They can be added along with a detergent to produce a tank-compatible record cleaning solution.

4. Antistats-
When to use: Vinyl records are insulators so they easily take on a static charge when put in contact with, and are separated from, other materials. As described in the Treating Static section above, chemical antistats can be used to make the record surface more conductive so that charges are neutralized and have less propensity for charge accumulation.

What to use: The most common antistats are quaternary ammonium compounds, and for record cleaning specifically the long alkyl chain “quat” surfactants. These are the same compounds found in hair conditioners, antistatic sprays, and dryer sheets. As many quats also exhibit biocidal activities, they are also found in commercial cleaners meant for hospitals, food service, and clean room facilities. Hence, pure quats like centriammonium chloride, behentriammonium chloride, or Quaternium-14 can be obtained from cosmetic supply houses or concentrated mixes of quats like octyl decyl dimethyl ammonium chloride, didecyl dimethyl ammonium chloride, and N-Alkyl dimethyl benzyl ammoniumchloride can be obtained from janitorial suppliers that carry “256 Quat” cleaning concentrates like Hepastat. When using a cleaning product, choose one with at least 20% quat content so that other non-essential or undesirable ingredients are diluted out in the mix.

How to use: Only a small amount of quat is required since the idea is to leave behind a molecular layer of the compounds on the record surface. If using in a mix with a non-ionic detergent, it is recommended to use the quat at 2 to 10 fold lower concentration than the detergent. If quat surfactants are to be used alone, they are typically included anywhere from 0.005-0.05 % range (the lower being in cases where no rinse if followed) as they also exhibit detergency. Never combine quats with solutions of anionic detergent (like dish soap) as they can form precipitates that diminish the antistat activity and even adhere to the record surface. For this same reason, quat solutions should only be stored in factory or new vessels, not any previously washed with another detergent. As they have biocidal activity, quat stocks can be stored at room temperature. In fact, some will flake out of solution at cold temperatures.


5. Disinfectants-
When to use: When handled and stored improperly, records can become infected with microorganisms like bacteria and fungi. While detergent can remove most of these contaminants, sometimes they are present in large amounts, often with spores and strongly adhered. Disinfectants might also be indicated when records are unavoidably stored a humid environment where they are continuously susceptible and there is a desire to prevent future infection. Microorganisms are present on dirty records because they utilize organic contaminants and sometimes even the vinyl ingredients as carbon sources. This can cause permanant damage to the record so disinfecting is of paramount importance.

What to use: There are a number of different compounds one can choose to battle microbial infections. As mentioned above, quats have biocidal properties so they are a great choice as they have the added anitstat benefit. For example, the quat benzalkonium chloride is the active ingredient in antiseptics like Bactine. Alcohols also have antiseptic properties but to kill microorganisms they need to be used at high concentrations (above 60%) where they may be detrimental to record composition. Another treatment is to utilize enzymes as they digest the compounds used by microbes to adhere to one another and to surfaces, allowing removal by detergent. The use of enzymes in record cleaning will be described in a subsequent section. Another class of disinfecting additives are chemical preservatives. Discwasher used to use the preservative sodium azide in their solution, but it is no longer common due to its toxicity. More common are thimersol, phenoxyethanol, and isothiazolinones.

How to use: The disinfectant is best included as part of a detergent washing solution. They are typically added at low concentrations (less than 0.1%). When included, they allow for cleaning mixes to be stored at room temperature. In devices where the cleaning solution is stored internally (an RCM, for example), it is good practice to include a quat or preservative in the solution so that the tank, pump, and tubing do not become contaminated with microbial growth.


6. Lubricants-
When to use: The surface of old records tend to dry out after years of environmental or chemical exposure. Some of this is due to autocatalytic breakdown of the PVC polymer itself, and neutralization of the acids built up in this reaction is of paramount importance. Another cause is the lack or reduction of lubricant, which calls for replenishment or “conditioning” so that the record plays without frictional noise.

What to use: The built-up acid in records can be removed or neutralized by simply washing. A wash solution with slightly basic pH (8 or 9) is useful, but most important is the dilutive effect of detergent washes followed by multiple water rinses. With regards to lubricant replacement, there are several commercial solutions sold for preserving vinyl records with this in mind. They typically include Polytetrafluorethylene, Polydimethylsiloxane, or various N-alkyl substituted dialkanolamine derivatives. Due to the complexity of solvents required to properly suspend and deliver these reagents to the record surface, it is difficult to recommend their use in a do-it-yourself solution. Because they bind strongly and are almost impossible to safely remove from the record surface, commercial products containing these chemicals (e.g. Last, Groovelube, etc.) might also be undesirable. The best alternative are solutions that rely on non-permanent coatings like the removable quat surfactants (with 16 carbon or longer “tails”) found in products like GruvGlide and the DIY solutions outlined above. Hence, a single additive like dimethyldioctadecylammonium chloride can function as an anti-stat, a sanitizer, and a restorative lubricant.

How to use: For commercial solutions, follow the recommended use. For DIY quat solutions, concentrations in the higher range (0.1-0.5% quat) are recommended and should be followed with pure water rinses as detergents can remove the surface-bound quat surfactants.